Preparation method of washable chitosan metal nanoparticle composite fiber
By spraying metal nanoparticles on the gel film and regenerating it after standing, combined with the wet twisting and shaping method, the problems of uneven distribution of metal nanoparticles and poor water washing resistance in chitin fibers were solved, and a composite fiber with excellent water washing resistance and functional durability was prepared, and the fiber properties can be adjusted.
Patent Information
- Application Number
- CN202311430627.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-10-29
- Publication Date
- 2025-09-12
- Estimated Expiration
- 2043-10-29
AI Technical Summary
When chitin is blended with metal nanoparticles, problems such as uneven particle distribution and poor water washability are likely to occur.
Chitosan/metal nanoparticle composite fibers with uniformly distributed metal nanoparticles were prepared by spraying metal nanoparticles on a gel film, allowing it to stand for a period of time before being regenerated in a coagulation bath. Combined with the wet twisting and shaping method, the standing time and stretching ratio were controlled.
The uniform dispersion of metal nanoparticles in the fiber is achieved, the water resistance of the fiber and the durability of the functional effect are improved, and the strength and toughness of the fiber can be changed by adjusting the standing time and stretching ratio.
Smart Images
Figure CN117468125B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of fiber materials, and in particular relates to a method for preparing washable chitosan metal nanoparticle composite fibers. Background Art
[0002] Chitin is the most abundant natural polymer in nature, second only to cellulose. It is primarily found in the cell walls of algae and fungi, as well as in the shells of shrimp, crabs, and insects. Chitin possesses excellent biocompatibility and biodegradability, making it an excellent biomaterial. However, due to the regular arrangement of molecular chains and the numerous intramolecular and intermolecular hydrogen bonds within its structure, chitin exhibits high crystallinity and a rich hydrogen-bonding network, making it insoluble in most common solvents.
[0003] Chitin fiber has excellent adsorption, antibacterial, and breathable properties. Textiles made from it can resist bacterial infections and prevent skin diseases. They are also odor-resistant, sweat-absorbing, and moisturizing, and are very comfortable to wear. Medical dressings made from chitin fiber can promote granulation and wound healing, and clinically have analgesic and hemostatic effects. Chitin fiber waste is naturally biodegradable and does not pollute the environment.
[0004] Currently, various forms of chitin fiber products are gaining increasing popularity in the textile and apparel sectors. Chitin fiber preparation technologies include wet spinning, dry spinning, wet-dry spinning, electrospinning, and fermentation. Currently, the most commonly used wet spinning technique involves dissolving chitin in a suitable solvent to create a spinning solution of a certain concentration, viscosity, and stable performance. After filtering and degassing, the spinning solution is sprayed through the small holes of a spinneret under a certain pressure into a coagulation bath. The thin stream of solution forms solid fibers in the coagulation bath, which are then stretched, washed, dried, and processed.
[0005] Chitosan composite fibers are typically produced by blending chitosan with other substances and then using wet spinning technology. However, when blended with metal nanoparticles, these fibers often suffer from uneven particle distribution in the spinning solution and poor washability. Based on this, the present invention provides a method for preparing chitosan / metal nanoparticle composite fibers with excellent washability and uniform distribution of metal nanoparticles. Summary of the Invention
[0006] In response to the shortcomings of the existing technology, the present invention provides a method for preparing washable chitin / metal nanoparticle composite fibers. The method comprises spraying metal nanoparticles on a gel film, wet-twisting the fibers to set the fibers, allowing the fibers to rest for a period of time before being regenerated in a specific coagulation bath, and then washing the fibers and airing the fibers to form fibers. The method enables the doped metal nanoparticles to be dispersed more evenly in the fibers, reduces particle agglomeration, and provides long-lasting functional effects imparted by wet-twisting the fibers after spraying, which maintain good effects even after multiple washes. Furthermore, the roughness and thickness of the fibers can be changed by controlling the resting time and the stretching ratio, thereby changing the fiber's properties such as strength and toughness.
[0007] In order to achieve the above object, the present invention adopts the following technical solutions:
[0008] A method for preparing washable chitin / nanoparticle composite fibers comprises at least the following steps:
[0009] S1: adding a cross-linking agent in a predetermined mass ratio to a chitosan solution, stirring and mixing, and forming a chitosan solution film of a certain thickness;
[0010] S2: preparing a nanoparticle solution of a predetermined concentration;
[0011] S3: The nanoparticle solution of S2 is attached to the surface of the chitosan solution film of S1, and the film is placed in an environment with a temperature of 10-50°C and a humidity of 20-80% for 3-6 hours to obtain a chitosan gel film;
[0012] S4: cutting the obtained chitosan gel film into thin strips of predetermined size, twisting and then stretching or stretching and then twisting and then standing for 0-1 hour to obtain gel-like chitosan fibers;
[0013] S5: placing the prepared gel-like chitosan fiber in a coagulation bath for regeneration for 1-12 hours, taking it out, washing it with clean water, and drying it to obtain chitosan / nanoparticle composite fibers.
[0014] Furthermore, in step S2, the concentration of the nanoparticle solution is 0.02-1.0 mg / ml, and the dispersion solution is isopropyl alcohol.
[0015] Furthermore, the nanoparticles of the nanoparticle solution are one or more combinations of silver nanowires, ferroferric oxide, copper oxide, silicon dioxide, carbon nanotubes, graphene, boron nitride, MOF, COF, etc.
[0016] Furthermore, the specific method of attaching the nanoparticle solution of S2 to the surface of the chitosan solution film of S1 is:
[0017] The nanoparticle solution prepared in S2 is sprayed onto a clean glass plate and left at room temperature for a predetermined time until the solvent evaporates.
[0018] Furthermore, the specific method of attaching the nanoparticle solution of S2 to the surface of the chitosan solution film of S1 is:
[0019] The nanoparticle solution prepared in S2 is sprayed onto the surface of the gel-like chitin fiber and left at room temperature for a predetermined time until the solvent evaporates.
[0020] Furthermore, the twisting is to twist the side of the chitosan gel film sprayed with the nanoparticle solution inward or outward.
[0021] Furthermore, the coagulation bath is one or more of methanol, ethanol, and propanol.
[0022] Furthermore, the cross-linking agent is 1-10% of the mass of the chitosan solution, and the cross-linking agent is epichlorohydrin.
[0023] Furthermore, the chitosan solution is prepared by first mixing KOH, urea, and distilled water in a predetermined weight ratio to prepare a mixed solution, and then dispersing 6 g of purified chitosan powder into 94 g of the mixed solution while stirring to obtain a suspension;
[0024] The suspension was frozen at -40°C for 6 hours and then thawed by vigorous stirring at room temperature. The freezing and thawing process was repeated twice, and the dissolved solution was centrifuged to obtain a transparent chitin solution.
[0025] Furthermore, the weight ratio of KOH, urea and distilled water is 15:4:75.
[0026] Compared with the prior art, the present invention has the following beneficial effects:
[0027] 1) The present invention sprays metal nanoparticles onto a gel film, wet-twistes the film to set the film, allows the film to rest for a period of time before regenerating it in a coagulation bath, and then washes and air-dries it into fibers. This method allows the doped metal nanoparticles to be more evenly dispersed in the fibers, reduces particle agglomeration, and avoids clogging of the spinneret by metal nanoparticles during wet spinning using a blending method. Furthermore, the method easily generates a large number of bubbles, which is detrimental to the smooth progress of the spinning process and results in poor fiber quality.
[0028] 2) The composite fiber prepared by spraying the functional material and then wet twisting has a long-lasting functional effect and good water washing resistance, and can still maintain good functional effects after multiple washings;
[0029] 3) The present invention can change the roughness and thickness of the fiber by controlling the standing time and the stretching ratio, thereby changing the properties of the fiber such as strength and toughness. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Figure 1is a production process flow chart of the preparation method of the present invention;
[0031] Figure 2 for Figure 1 3D microscope image of the finished product prepared from the production process flow chart;
[0032] Figure 3 a in the middle is press Figure 1 a is a flow chart of the production process flow chart of the washable chitin / metal nanoparticle composite fiber prepared by Figure 1 A physical picture of the washable chitin / metal nanoparticle composite fiber prepared by the production process flow chart;
[0033] Figure 4 Graph showing roughness R with respect to parameters D and L in an embodiment of the present invention. DETAILED DESCRIPTION
[0034] The present invention will be further described in detail below with reference to specific embodiments so that those skilled in the art can understand the present invention more clearly.
[0035] Example 1
[0036] like Figure 1 As shown, the preparation method of the washable chitosan metal nanoparticle composite fiber in this embodiment is as follows:
[0037] 1) KOH, urea, and distilled water were mixed at a weight ratio of 15:4:75 to prepare a 15 wt% KOH, 4 wt% urea aqueous solution, and then 6 g of purified chitosan powder was dispersed in 94 g of the KOH / urea aqueous solution while stirring to obtain a suspension;
[0038] 2) Freeze the suspension in a cold trap (-40°C) for 6 hours, then thaw it with vigorous stirring at room temperature. Repeat the freezing and thawing process twice, and then centrifuge the solution to obtain a transparent chitin solution.
[0039] 3) Weigh 50 g of the transparent chitosan solution prepared in step 2) and place it in a pre-prepared ice-water bath. Add 2 g of epichlorohydrin (ECH) as a crosslinking agent to the chitosan solution while stirring. After 0.5 hour, centrifuge the crosslinked chitosan solution to remove bubbles generated during stirring.
[0040] 4) The solution obtained by centrifugation in step 3) was evenly spread by casting on a glass plate sprayed with 20 ml of a 1 mg / ml AgNW solution (isopropanol as a dispersant). The solution was allowed to stand for 6 hours to form a gel film. 20 ml of a 1 mg / ml AgNW solution (isopropanol as a dispersant) was then sprayed on the surface of the gel film.
[0041] 5) Use a scalpel to cut the gel film from step 4) into long strips (10 cm long and 0.5 cm wide). Twist the strips into threads, let them stand for a certain period of time (0 min), and then place them in a methanol coagulation bath for 12 hours. Finally, wash the chitin threads with clean water three times and air-dry them.
[0042] Examples 2-5
[0043] The preparation method of the washable chitin / metal nanoparticle composite fiber provided in Example 2-5 is different from that in Example 1, except that the standing time in step 5 is changed. Except for the above differences, other operations are the same and will not be repeated here. The specific experimental conditions and measurement results are shown in Table 1.
[0044] It should be noted that the present invention was obtained using a 5943 universal material testing machine from INSTRON, USA. Before the test, the composite fiber was balanced for 12 hours at a temperature of 23°C and a humidity of 65%. During the test, the sample was stretched at a speed of 20 mm / min and the test length was 20 mm, that is, under pre-tension, the length of the fiber sample was 20 mm.
[0045] Wherein, the roughness R=L / D, and the lengths of D and L are measured by Nano Measurer software, as shown in Figure 4 shown.
[0046] Table 1
[0047]
[0048] Comparing the results of Example 1 with Examples 2-5, it can be seen that the composite material's elongation at break and stress increase with increasing rest time. This phenomenon occurs because the reaction time between chitin and the crosslinking agent increases with increasing rest time, resulting in more hydrogen bonds forming in the network structure formed by the organic matter. The macromolecular interactions between the molecular chains ensure the composite material's high strain resistance.
[0049] Example 6
[0050] 1) KOH, urea, and distilled water were mixed at a weight ratio of 15:4:75 to prepare a 15 wt% KOH, 4 wt% urea aqueous solution, and then 6 g of purified chitosan powder was dispersed in 94 g of the KOH / urea aqueous solution while stirring to obtain a suspension;
[0051] 2) Freeze the suspension in a cold trap (-40°C) for 6 hours, then thaw it with vigorous stirring at room temperature. Repeat the freezing and thawing process twice, and then centrifuge the solution to obtain a transparent chitin solution.
[0052] 3) Weigh 50 g of the solution prepared in step 2) and place it in a pre-prepared ice-water bath. Add 2 g of epichlorohydrin (ECH) as a cross-linking agent to the chitin solution while stirring. After 0.5 hour, centrifuge the cross-linked chitin solution to remove bubbles generated during stirring.
[0053] 4) The solution obtained by centrifugation in step 3) was evenly spread by casting on a glass plate sprayed with 20 ml of a 1 mg / ml AgNW solution (isopropanol as a dispersant). The solution was allowed to stand for 6 hours to form a gel film. 20 ml of a 1 mg / ml AgNW solution (isopropanol as a dispersant) was then sprayed on the surface of the gel film.
[0054] 5) Use a scalpel to cut the gel film from step 4) into strips (10 cm long and 0.5 cm wide). Twist and stretch the strips into filaments at a stretch ratio of 100%. Let them stand for 20 minutes and then place them in a methanol coagulation bath for 12 hours. Finally, wash the strips three times with clean water and air dry.
[0055] Examples 7-10
[0056] The preparation method of the washable chitin / metal nanoparticle composite fiber provided in Examples 7-10 is different from that in Example 6, except that the stretching ratio in step 5 is changed. Except for the above differences, other operations are the same and will not be repeated here. The specific experimental conditions and measurement results are shown in Table 2.
[0057] Table 2
[0058]
[0059] Comparing the results of Example 6 with Examples 7-10, we can see that as the draw ratio increases, the breaking strength increases while the elongation at break decreases. When the draw ratio is 100% and the fiber is left standing for 20 minutes, it reaches its maximum breaking strength of 140 MPa. This phenomenon occurs because as the draw ratio increases, the crystallinity of the sample increases, leading to an increase in breaking strength and a decrease in elongation at break.
[0060] The composite fibers prepared in Examples 6-10 were subjected to a water-washing resistance and conductivity test. The test results are shown in Table 3.
[0061] Table 3
[0062]
[0063] The results of the water-washing resistance conductivity test (Table 3) show that the chitosan / metal nanoparticle composite fiber prepared by the present invention has excellent conductivity and still has good conductivity after being washed 50 times.
[0064] The above is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A method for preparing washable chitosan / nanoparticle composite fibers, characterized in that: At least the following steps are included: S1: adding a cross-linking agent in a predetermined mass ratio to a chitosan solution, stirring and mixing, and forming a chitosan solution film of a certain thickness; S2: preparing a nanoparticle solution of a predetermined concentration; S3: The nanoparticle solution of S2 is attached to the surface of the chitosan solution film of S1, and the film is placed in an environment with a temperature of 10-50°C and a humidity of 20-80% for 3-6 hours to obtain a chitosan gel film; S4: cutting the obtained chitosan gel film into thin strips of predetermined size, twisting and then stretching or stretching and then twisting and then standing for 0-1 hour to obtain gel-like chitosan fibers; S5: placing the prepared gel-like chitosan fiber in a coagulation bath for regeneration for 1-12 hours, taking it out, washing it with clean water, and drying it to obtain chitosan / nanoparticle composite fibers.
2. The preparation method according to claim 1, characterized in that In step S2, the concentration of the nanoparticle solution is 0.02-1.0 mg / ml, and isopropyl alcohol is used as the dispersion solution.
3. The preparation method according to claim 2, characterized in that The nanoparticles in the nanoparticle solution are one or more combinations of silver nanowires, ferroferric oxide, copper oxide, silicon dioxide, carbon nanotubes, graphene, boron nitride, MOF, and COF.
4. The preparation method according to claim 1, characterized in that The specific method of attaching the nanoparticle solution of S2 to the surface of the chitin solution film of S1 is: The nanoparticle solution prepared in S2 is sprayed onto the surface of the chitosan solution film and left at room temperature for a predetermined time until the solvent evaporates.
5. The preparation method according to claim 1, characterized in that The twisting is to twist the side of the chitosan gel film sprayed with the nanoparticle solution inward or outward.
6. The preparation method according to claim 1, characterized in that The coagulation bath is one or more of methanol, ethanol and propanol.
7. The preparation method according to claim 1, characterized in that The cross-linking agent accounts for 1%-10% of the mass of the chitosan solution, and the cross-linking agent is epichlorohydrin.
8. The preparation method according to claim 7, characterized in that The chitosan solution is prepared by mixing KOH, urea, and distilled water in a predetermined weight ratio to prepare a mixed solution, and then dispersing 6 g of purified chitosan powder into 94 g of the mixed solution while stirring to obtain a suspension. The suspension was frozen at -40°C for 6 hours and then thawed by vigorous stirring at room temperature. The freezing and thawing process was repeated twice, and the dissolved solution was centrifuged to obtain a transparent chitin solution.
9. The preparation method according to claim 8, characterized in that The weight ratio of KOH, urea and distilled water is 15:4:75.