A method for modifying polyester fabric based on lipase and titanium dioxide nanorod combination

Abstract

The application discloses a method for modifying polyester fabric based on lipase and titanium dioxide nanorod combination, and belongs to the field of textile technology. The application first adopts lipase to treat the polyester fabric, so that the surface of the polyester fabric forms polar groups such as hydroxyl groups or carboxyl groups; then, the suspended and positively charged titanium dioxide particles are combined on the surface of the polyester fabric through chemical bonds, thereby improving the adhesion of titanium dioxide and having little influence on the performance of the polyester fabric. Moreover, compared with loading TiO2 on the surface of the fabric or adding TiO2 in the melt spinning of the fabric, the application directly loads TiO2 in situ by forming hydroxyl groups on the surface of the polyester fabric through the biological enzyme, thereby improving the combination firmness with the polyester fabric. Compared with 0-dimensional TiO2 nanoparticles, 1-dimensional TiO2 nanorods can greatly improve the hydrophilicity, ultraviolet resistance and other functions of the polyester fabric, and can form a more uniform TiO2 nanorod film on the surface of the polyester fabric.

Description

Technical Field

[0001] This invention relates to a method for modifying polyester fabrics based on the combined use of lipase and titanium dioxide nanorods, belonging to the field of textile technology. Background Technology

[0002] Nano-titanium dioxide (TiO2) is an important inorganic functional nanomaterial. Due to its advantages such as transparency and non-toxicity, gas sensitivity, humidity sensitivity, ultraviolet absorption, high catalytic activity, strong oxidation capacity, and good performance stability, it is widely used in sunscreen cosmetics, advanced coatings, self-cleaning materials, and photocatalytic degradation of atmospheric and water pollutants. The development and application of nanotechnology have also provided new opportunities for the functionalization of textile materials, especially in the development and research of functional textile materials with antibacterial, anti-ultraviolet radiation, and antistatic properties.

[0003] Since TiO2 is a nanoparticle, it needs to be loaded onto a carrier during use. This carrier can be an inorganic material such as glass or metal sheet, or an organic polymer material such as resin or textile fiber. Currently, combining titanium dioxide nanoparticles with textiles can endow textile materials with excellent properties such as UV resistance, hydrophilicity, and photocatalysis. The adhesion mechanism between conventional titanium dioxide and fabrics is generally divided into physical and chemical mechanisms. Physical adhesion of TiO2 to fabrics can cause it to detach during use or washing, resulting in the loss of the functional layer. Chemical adhesion can make TiO2 adhere more firmly to the fabric surface and reduce detachment during use, but it can damage the fabric.

[0004] Therefore, how to improve the bonding strength between TiO2 and textile materials while reducing damage to the fabric is an urgent problem to be solved. Summary of the Invention

[0005] [Technical Issues]

[0006] Simply loading titanium dioxide onto the surface of polyester fabric is prone to detachment;

[0007] Simply using biological enzymes to modify the hydrophilicity of polyester is ineffective; it can only improve the hydrophilicity of polyester but cannot achieve superhydrophilicity.

[0008] [Technical Solution]

[0009] To address the aforementioned issues, this invention first treats polyester fabric with lipase to form polar groups such as hydroxyl or carboxyl groups on the fabric surface. Then, suspended and positively charged titanium dioxide particles are chemically bonded to the polyester fabric surface, thereby improving the adhesion of titanium dioxide while having minimal impact on the properties of the polyester fabric itself. Furthermore, compared to loading TiO2 onto the fabric surface or adding TiO2 during melt spinning, this invention uses a bio-enzyme to form hydroxyl groups on the polyester fabric surface, allowing for direct in-situ loading of TiO2 and improving the bonding strength with the polyester fabric. Compared to zero-dimensional TiO2 nanoparticles, one-dimensional TiO2 nanorods can significantly enhance the hydrophilicity and UV resistance of polyester fabrics, and can form a more uniform TiO2 nanorod film on the polyester fabric surface. Moreover, there are no prior reports in the literature regarding the loading of one-dimensional TiO2 nanorods onto enzymatically treated polyester fabrics.

[0010] The first objective of this invention is to provide a method for modifying polyester fabrics based on a combination of lipase and titanium dioxide nanorods, comprising the following steps:

[0011] (1) Lipase treatment:

[0012] The refined polyester fabric is immersed in a lipase solution, and then Tween 80 is added to carry out the reaction. After the reaction is completed, the fabric is taken out, washed, and dried to obtain the lipase-treated polyester fabric.

[0013] (2) Titanium sol treatment:

[0014] Tetrabutyl titanate, water, concentrated nitric acid and anhydrous ethanol were mixed evenly to obtain a titanium sol solution; the lipase-treated polyester fabric was immersed in the titanium sol solution and then removed to obtain titanium sol-treated polyester fabric.

[0015] (3) Acid solution treatment:

[0016] The titanium sol-treated polyester fabric was immersed in hydrochloric acid solution for reaction; after the reaction was completed, it was taken out, washed, and dried to obtain the acid-treated polyester fabric.

[0017] (4) Growth of nano-titanium dioxide nanorods:

[0018] Titanium source was added to concentrated hydrochloric acid aqueous solution and mixed evenly to obtain titanium dioxide nanorod growth solution; then, the acid-treated polyester fabric was immersed in titanium dioxide nanorod growth solution and reacted at 110-120℃ for 4-7h; after the reaction was completed, it was taken out, washed and dried to obtain polyester fabric modified by lipase and titanium dioxide nanorods.

[0019] In one embodiment of the present invention, the method for preparing the refined polyester fabric in step (1) is as follows:

[0020] The polyester fabric is placed in a solution of soap flakes and sodium carbonate for desizing, sizing, washing, drying, and equilibration in a constant temperature and humidity chamber to obtain a refined polyester fabric.

[0021] In the soap flakes and sodium carbonate solution, the concentration of soap is 4-6 g / L, the concentration of sodium carbonate is 3-5 g / L, and the solvent is water.

[0022] The bath ratio for desizing and simmering is 1:20-50, the temperature is 95-100℃, and the time is 20-40 minutes.

[0023] The cleaning process involves using water.

[0024] Drying is carried out at 100-105℃;

[0025] The constant temperature and humidity chamber should be equilibrated at 25±1℃ and 65±2% for at least 24 hours.

[0026] In one embodiment of the present invention, the bath ratio of lipase treatment in step (1) is 1:20-50; the lipase solution is an aqueous solution of lipase, and the concentration of lipase is 60-100 U / mL; the concentration of Tween 80 in the lipase solution is 1-3 g / L; and the reaction is carried out at 50-70°C for 12-36 h.

[0027] In one embodiment of the present invention, the lipase activity in step (1) is 100-500 U / mg and is purchased from Sigma.

[0028] In one embodiment of the present invention, the washing in step (1) is performed sequentially with sodium dodecyl sulfate, anhydrous ethanol, and water.

[0029] In one embodiment of the present invention, the molar ratio of tetrabutyl titanate, water, concentrated nitric acid and anhydrous ethanol in step (2) is 1:1:0.1:9.25; the mixture is stirred at 500-1000 rpm for 1-2 hours to achieve uniform mixing.

[0030] In one embodiment of the present invention, the bath ratio of titanium sol treatment in step (2) is 1:20-50, the temperature is 20-30℃ (room temperature), and the time is 12-36h.

[0031] In one embodiment of the present invention, the hydrochloric acid solution in step (3) is an aqueous hydrochloric acid solution with a concentration of 0.1-0.5 mol / L.

[0032] In one embodiment of the present invention, the bath ratio in step (3) is 1:20-50, the temperature is 50-80℃, and the time is 12-36h.

[0033] In one embodiment of the present invention, the concentrated hydrochloric acid aqueous solution in step (4) is obtained by mixing concentrated hydrochloric acid and water at a volume ratio of 1:1-3 and stirring at 500-1000 rpm for 10-30 min.

[0034] In one embodiment of the present invention, the titanium source in step (4) is tetrabutyl titanate.

[0035] In one embodiment of the present invention, the mass fraction of the titanium source in the concentrated hydrochloric acid aqueous solution in step (4) is 1-5%.

[0036] In one embodiment of the present invention, the bath ratio in step (4) is 1:20-50.

[0037] The second objective of this invention is to prepare polyester fabrics modified with lipase and titanium dioxide nanorods using the method described herein.

[0038] The third objective of this invention is the application of the lipase and titanium dioxide nanorods combined to modify polyester fabrics as described in this invention in the textile field.

[0039] In one embodiment of the invention, the application is for household textiles or industrial textiles.

[0040] A fourth objective of this invention is to provide a textile fabric prepared by using the lipase and titanium dioxide nanorods described in this invention to modify polyester fabric.

[0041] [Beneficial Effects]

[0042] (1) In this invention, lipase treatment is first used to form polar groups such as hydroxyl or carboxyl groups on the surface of polyester fabric; then, suspended and positively charged titanium dioxide particles are chemically bonded to the surface of polyester fabric, thereby improving the adhesion of titanium dioxide.

[0043] (2) The method of the present invention enables the in-situ growth of TiO2 one-dimensional nanorods on lipase-treated polyester fabric, forming a dense and uniform layer of TiO2 one-dimensional nanorods on the fabric surface; this endows the polyester fabric with excellent hydrophilicity, as well as superior UV protection and photocatalytic properties, making the lipase and titanium dioxide nanorods combined modified polyester fabric a promising candidate for applications in clothing, UV protection and photocatalysis. Attached Figure Description

[0044] Figure 1 SEM images of the polyester fabrics prepared in Comparative Example 1(a) and Example 1(b).

[0045] Figure 2 The K / S values ​​of the polyester fabrics prepared for comparative examples 1 and 2 after methylene dyeing are shown in the diagram.

[0046] Figure 3 The image shows the XRD pattern of the polyester fabric prepared in Example 1.

[0047] Figure 4 Contact angle test results for untreated polyester fabric (a), Comparative Example 1 (b), and Example 1 (c).

[0048] Figure 5 UV protection rate diagrams for polyester fabrics prepared in Comparative Example 1 and Example 1.

[0049] Figure 6 This is a SEM image of the surface of polyester fabric prepared by growing titanium dioxide nanorods at different temperatures in Example 2.

[0050] Figure 7 The image shows SEM images of the surface of polyester fabric prepared by growing titanium dioxide nanorods at different times in Example 3.

[0051] Figure 8 SEM image of the surface of the polyester fabric prepared in Comparative Example 4.

[0052] Figure 9 Physical image (a) and surface SEM image (b) of the polyester fabric prepared for Comparative Example 5. Detailed Implementation

[0053] The preferred embodiments of the present invention are described below. It should be understood that the embodiments are for better explanation of the present invention and are not intended to limit the present invention.

[0054] Test method:

[0055] 1. Test method for water contact angle:

[0056] The polyester fabric to be tested was placed in a constant temperature and humidity chamber (25±1℃, 65±2%) for at least 24 hours to equilibrate, and the corresponding water contact angle was obtained by using a DSA 25 contact angle measuring instrument.

[0057] Specifically, five different locations on the polyester fabric to be tested were cut with scissors and sampled. The samples were then attached to a glass slide with double-sided tape. A water droplet (10 μL) was dropped 10 mm from the fabric surface. The contact angle was observed through the instrument display and photographed. The average value of the results was taken as the average water contact angle.

[0058] 2. Observation of surface microstructure:

[0059] After the surface of the polyester fabric to be tested was plated with gold, the changes in the surface morphology of the polyester fabric fibers were observed using an SU 8100 scanning electron microscope with an accelerating voltage of 5.0 kV.

[0060] 3. Phase characterization of the fabric:

[0061] The surface of the polyester fabric under test was tested using a D2 PHASER X-ray diffractometer with a scanning angle of 5-90°.

[0062] 4. UV resistance characterization of fabrics:

[0063] The UV-2000F fabric UV transmittance tester was used to test the surface UV protection effect of the polyester fabric under test.

[0064] 5. Characterization of the mechanical properties of polyester fabrics for wearing:

[0065] The tensile breaking test of the polyester fabric under test was carried out using an HD026NS-200 multifunctional electronic fabric tensile tester; specifically: the test interval was 50mm and the tensile speed was 100mm / min.

[0066] The PhabrOmeter fabric style tester was used to perform fabric style testing on the polyester fabric under test.

[0067] Abrasion resistance tests were conducted on the fabrics to be tested using a YG(B)401 Martindale abrasion tester.

[0068] The air permeability of the fabric under test was tested using a YG461E fully automatic air permeability meter.

[0069] 6. Fabric methylene blue dyeing test

[0070] Polyester fabrics treated with lipase and control samples were dyed. Methylene blue is an alkaline dye that can be adsorbed onto the -COO- groups on the surface of polyester fabrics, so it can be used to detect changes in the number of -COOH groups on the surface.

[0071] The dyeing process was as follows: the concentration of methylene blue dye was 0.5% owf, the liquor ratio was 1:100, and dyeing was carried out in a constant temperature shaking chamber (150 rpm, 60℃) for 2 hours. The dyed polyester fabric was rinsed with deionized water and dried at room temperature.

[0072] The dyeing properties of polyester fabrics before and after enzyme treatment were tested using a Datacolor colorimeter and Datacolor TOOLS Plus software. Specifically, the polyester fabric to be tested was folded twice, and the X, Y, and Z values ​​of the sample were measured in the visible region using a 10° standard observer under a D65 light source, with a wavelength range of 360-700 nm, utilizing the maximum absorption wavelength (λ). max The K / S value of the fabric is calculated by measuring the reflectance at a certain point.

[0073] 7. Characterization of the photocatalytic fading effect of fabrics

[0074] The photocatalytic fading of fabrics was tested using a Datacolor 650 spectrophotometer; the specific procedures are as follows:

[0075] The fabric to be tested was immersed in 20 mL of methylene blue solution (mass fraction of 0.05%) for 3 min, dried at room temperature in the dark, and then irradiated with ultraviolet light or sunlight (ultraviolet light was irradiated with a 10W ultraviolet crosslinker for 2 h; sunlight irradiation was selected between 12:00 and 16:00 in August for 2 h). The parameters L, a, b, R, G, and B of the fabric before and after irradiation were tested with a colorimeter, and the photocatalytic fading effect was calculated using formulas (1)-(2), as follows:

[0076]

[0077]

[0078] Wherein, R1, G1, B1 and R2, G2, B2 are the R, G, and B values ​​of the fabric before and after irradiation by the light source, respectively. The higher the ΔE and ΔRGB values, the better the photocatalytic fading effect of methylene blue on the fabric.

[0079] Raw materials used in the examples and comparative examples:

[0080] Polyester fabric: 100% polyester filament plain weave fabric, both warp and weft yarns are 2.22 tex, warp and weft densities are 880 / 680 threads / (10cm) respectively, and areal density is 56 g / m². 2 ;

[0081] The refined polyester fabric is prepared by placing it in a solution of 5 g / L soap flakes and 4 g / L sodium carbonate at a liquor ratio of 1:30 and desizing and boiling at 98°C for 30 min; then washing with deionized water, drying at 105°C, and finally placing the polyester fabric in a constant temperature and humidity chamber (25±1°C, 65±2%) for at least 24 h to obtain the refined polyester fabric.

[0082] Water: Deionized water;

[0083] Lipase: Enzyme activity 100-500 U / mg, purchased from Sigma;

[0084] In the examples and comparative examples, solutions for which the solvent is not specifically specified are water; and unless otherwise specified, % refers to mass percentage.

[0085] Example 1

[0086] A method for modifying polyester fabrics based on lipase and titanium dioxide nanorods includes the following steps:

[0087] (1) Lipase treatment:

[0088] The refined polyester fabric was immersed in an 80 U / mL lipase solution at a liquor ratio of 1:40, and then Tween 80 (content of 2 g / L) was added. The reaction was carried out at 60℃ for 24 h. After the reaction was completed, the fabric was taken out and washed with sodium dodecyl sulfate, anhydrous ethanol and deionized water in sequence, and dried at 105℃ to obtain the lipase-treated polyester fabric.

[0089] (2) Titanium sol treatment:

[0090] Tetrabutyl titanate, water, concentrated nitric acid and anhydrous ethanol were mixed at a molar ratio of 1:1:0.1:9.25 at 900 rpm for 1 h to obtain a titanium sol solution.

[0091] The lipase-treated polyester fabric was immersed in a titanium sol solution at room temperature for 24 hours at a bath ratio of 1:40, and then removed to obtain titanium sol-treated polyester fabric.

[0092] (3) Acid solution treatment:

[0093] The polyester fabric treated with titanium sol was immersed in a 0.1 mol / L hydrochloric acid solution at a bath ratio of 1:40 and reacted at 80°C for 24 hours. After the reaction was completed, the fabric was taken out, washed with water, and dried at 80°C to obtain the acid-treated polyester fabric.

[0094] (4) Growth of nano-titanium dioxide nanorods:

[0095] Concentrated hydrochloric acid and water were stirred at 900 rpm for 10 min at a volume ratio of 1:1 to obtain a concentrated hydrochloric acid aqueous solution. Then, tetrabutyl titanate (mass fraction of 2%) was added to the concentrated hydrochloric acid aqueous solution and stirred at 900 rpm for 20 min to obtain a titanium dioxide nanorod growth solution. The acid-treated polyester fabric was then immersed in the titanium dioxide nanorod growth solution at a bath ratio of 1:40 and reacted in a muffle furnace at 120 °C for 7 h. After the reaction was completed, the fabric was removed, washed with water, and dried at 105 °C to obtain a polyester fabric co-modified with lipase and titanium dioxide nanorods.

[0096] Comparative Example 1

[0097] Steps (2)-(4) of Example 1 are omitted, and only lipase treatment is used, which is consistent with Example 1, to obtain lipase-treated polyester fabric.

[0098] Comparative Example 2

[0099] Omit Tween 80 in Comparative Example 1, and keep everything else the same as in Comparative Example 1 to obtain polyester fabric treated with only enzyme.

[0100] Comparative Example 3

[0101] Adjust steps (2)-(4) of Example 1 as follows:

[0102] TiO2 nanoparticles were dispersed in water, the pH was adjusted to neutral (7-8), and the mixture was sonicated for 30 min to obtain 50 mL of finishing solution.

[0103] The polyester fabric treated with lipase was immersed in the finishing solution at room temperature with a bath ratio of 1:40, and then dipped and rubbed twice. Each dip lasted for 10 minutes and the roll-off rate was 90%. The fabric was washed twice with deionized water and dried at 80°C to obtain the enzymatically treated polyester fabric finished with TiO2 nanoparticles.

[0104] The polyester fabrics obtained in Example 1 and Comparative Examples 1-3 were subjected to performance tests, and the test results are as follows:

[0105] Figure 1 SEM images of the polyester fabrics prepared in Comparative Example 1(a) and Example 1(b). From Figure 1 It can be seen that: in Comparative Example 1, the surface of the polyester fabric treated with lipase showed an etching phenomenon, which was formed by the hydrolysis of polyester by lipase; the ester bonds of polyester hydrolyzed by lipase formed hydroxyl and carboxyl groups on the fabric surface; the polyester fabric modified by lipase and titanium dioxide nanorods prepared in Example 1 had a layer of titanium dioxide nanorods on its surface, which was dense and uniformly distributed.

[0106] Figure 2 The K / S value graph shows the results of methylene dyeing on the polyester fabrics prepared in Comparative Examples 1 and 2. Figure 2 It can be seen that the K / S value of polyester fabrics treated with lipase-Tween 80 increased in the 550-650 nm range, confirming that lipase hydrolyzed the polyester fabric. The significant increase in the K / S value of the polyester fabric after lipase-Tween treatment indicates that the hydrolysis of the polyester fabric resulted in an increase in the number of -COOH end groups, leading to a significant increase in the adsorption of methylene blue dye on the polyester fabric surface. Due to the increase in -COOH end groups after hydrolysis, the polar groups on the fabric surface increased, resulting in increased adhesion between TiO2 and the fabric in the later stages.

[0107] Figure 3 The image shows the XRD pattern of the polyester fabric prepared in Example 1. Figure 3It can be seen that the main diffraction peaks of the polyester fabric modified by lipase and titanium dioxide nanorods prepared in Example 1 are 2θ = 17.7, 22.5, 25.3, 26.1, 27.4, 36.1, 41.2, 41.7, 54.3, 56.2, 62.7, 69.0, 69.8. According to JADA6.0, 2θ = 17.7, 22.5, 26.1, 41.7 are the (010), (011), and (021) crystal planes of polyester, respectively; 2θ = 25.3 is the (101) crystal plane of anatase TiO2; and 2θ = 27.4, 36.1, 41.2, 54.3, 56.2, 62.7, 69.0, 69.8 are the (110), (101), (111), (211), (220), (002), (301), and (112) crystal planes of rutile TiO2, respectively.

[0108] Figure 4 Contact angle test results for polyester fabrics prepared for untreated polyester fabric (a), Comparative Example 1 (b), and Example 1 (c). Figure 4 It can be seen that the 60s water contact angle of the untreated polyester fabric surface is 108°; the 60s water contact angle of the polyester fabric surface treated with lipase prepared in Comparative Example 1 is 86.6°. This is because the active groups on the fabric surface are increased, resulting in a lower water contact angle. The water contact angle of the polyester fabric modified by the lipase and titanium dioxide nanorods prepared in Example 1 is 0° at 2s, achieving superhydrophilic modification of the fabric.

[0109] Figure 5 UV protection rate graphs for the polyester fabrics prepared in Comparative Example 1 and Example 1. From... Figure 5 It can be seen that the UV transmittance of the enzymatically treated fabric in Comparative Example 1 gradually increases from the UV wavelength of 310 nm, and reaches a maximum of 22.5% at 380 nm. The UV transmittance of the polyester fabric modified by lipase and titanium dioxide nanorods prepared in Example 1 remains at 0% between 290 and 390 nm, increases from 395 nm, and reaches a maximum of 8% at 440 nm, thus achieving the UV protection performance of the polyester fabric.

[0110] Table 1 characterizes the photocatalytic fading effect of polyester fabrics in Example 1 and Comparative Examples 1 and 3. As shown in Table 1, the ΔE for the degradation of methylene blue by the lipase and titanium dioxide nanorod modified polyester fabric prepared in Example 1 under ultraviolet light and sunlight was 43.35 and 37.25, respectively, and the ΔRGB values ​​were 87.67 and 78.9, respectively. Compared with the enzymatically treated polyester fabric in Comparative Example 1, the ΔE and ΔRGB values ​​of the lipase and titanium dioxide nanorod modified polyester fabric in Example 1 increased by 39.95 and 76.87 under ultraviolet light, respectively, and increased by 2 under sunlight, respectively. 8.55, 60.17; Compared with polyester fabric treated with nano-TiO2 particles, the polyester fabric modified with lipase and titanium dioxide nanorods in Example 1 showed that ΔE and ΔRGB increased by 24.8 and 61.9 respectively under ultraviolet light, and by 22.52 and 56.89 respectively under sunlight; The results show that the polyester fabric modified with lipase and titanium dioxide nanorods prepared in Example 1 has a significantly improved photocatalytic fading effect on methylene blue, indicating that it has a significant photocatalytic self-cleaning effect.

[0111] Table 1. Characterization of the photocatalytic fading effect of polyester fabrics in Example 1 and Comparative Examples 1 and 3.

[0112]

[0113] Table 2 shows the UV protection efficacy tests of the polyester fabrics in Example 1 and Comparative Examples 1 and 3.

[0114]

[0115] Table 2 shows the UV protection efficacy tests of the polyester fabrics in Example 1 and Comparative Examples 1 and 3. As can be seen from Table 2, the UVA%, UVB%, and UPF of the polyester fabric modified with lipase and titanium dioxide nanorods prepared in Example 1 were 0.15%, 0.05%, and 340.56%, respectively. Compared to the polyester fabric treated with nano-TiO2 particles in Comparative Example 3, the UVA% of the polyester fabric modified with lipase and titanium dioxide nanorods prepared in Example 1 decreased by 8.58%, the UVB% decreased by 0.33, and the UPF increased by 252.89. According to GB / T 18830 "Evaluation of Ultraviolet Protection Performance of Textiles," a product can only be called a "UV-protective product" if its UPF value is greater than 40 and its UVA transmittance is less than 5%; both conditions are indispensable. Therefore, the polyester fabric modified with lipase and titanium dioxide nanorods prepared in Example 1 possesses excellent UV protection performance.

[0116] Table 3 shows the 60-second contact angle test results of the polyester fabric modified with lipase and titanium dioxide nanorods prepared in Example 1 after repeated washing and drying 10 times. As can be seen from Table 3, the average 60-second water contact angle of the polyester fabric modified with lipase and titanium dioxide nanorods prepared in Example 1 after ultrasonic washing for 10 minutes, 10 washes, and 10 drying cycles was 9°. Although the contact angle increased compared to before washing, its hydrophilicity remained at a good level. This demonstrates that the polyester fabric modified with lipase and titanium dioxide nanorods has good wash fastness and excellent wash resistance.

[0117] Table 3. Test data of wash fastness in Example 1

[0118] fabric Before washing After washing 10 times Water contact angle at 60s (°) 0 9

[0119] Table 4 shows the test results of the abrasion resistance of the polyester fabric modified with lipase and titanium dioxide nanorods prepared in Example 1. As can be seen from Table 4, after 500 friction cycles, the average water contact angle of the polyester fabric modified with lipase and titanium dioxide nanorods prepared in Example 1 was 10° at 60s. Although this is slightly higher than before friction, its hydrophilicity remains at a good level, demonstrating that the polyester fabric modified with lipase and titanium dioxide nanorods has excellent abrasion resistance.

[0120] Table 4. Test results of abrasion resistance of polyester fabrics modified with lipase and titanium dioxide nanorods prepared in Example 1.

[0121] Friction cycles (times) 0 times 100 times 200 times 300 times 400 times 500 times Water contact angle at 60s (°) 0 2 5 5 8 10

[0122] Table 5. Results of the efficacy tests for Example 1 and Comparative Example 1

[0123]

[0124] Table 5 shows the test results of the wearing performance of the polyester fabrics prepared in Example 1 and Comparative Example 1. As can be seen from Table 5, the lipase and titanium dioxide nanorod modified polyester fabric prepared in Example 1 has a warp breaking strength of 315.7 N and an elongation at break of 20.9%, and a weft breaking strength of 215.6 N and an elongation at break of 17.24%. The warp strength loss was 6.7%, and the elongation at break was 20.0%; the weft strength loss was 10.9%, and the elongation at break was 18.0%, still maintaining the good mechanical properties of polyester fabric. The air permeability was improved compared to the enzymatically treated fabric of Comparative Example 1. The air permeability decreased from 20.24 mm / s to 15.89 mm / s, resulting in a 21.4% loss. This is because the growth of nanorods occupied some of the space between fabric layers. The sensory scores for stiffness, softness, and smoothness of the fabric in Example 1 were 43.33, 67.75, and 85.69, respectively. Compared to the enzymatically catalyzed fabric of Comparative Example 1, stiffness increased by 21.3%, softness decreased by 6.9%, and smoothness increased by 5.1%. This indicates that the fabric in Example 1 is stiffer, softer, and smoother. The results show that the polyester fabric in Example 1 has better wearing performance.

[0125] Example 2

[0126] The reaction temperature in step (4) of Example 1 was adjusted to 95, 100, 105, 110, 115, 120, 125, and 130°C, while other conditions remained the same as in Example 1, to obtain polyester fabric modified by lipase and titanium dioxide nanorods.

[0127] The obtained lipase and titanium dioxide nanorods were combined to modify polyester fabric, and the performance was tested. The test results are as follows: Figure 6 :

[0128] from Figure 6 It can be seen that as the temperature for growing titanium dioxide nanorods increases, the nanoseed layer on the surface of the polyester fabric gradually nucleates, the nanorods grow, the nanorod density gradually increases, and the nanorod diameter first increases and then decreases. More specifically, no nanorods are formed on the fabric surface at 95℃, the fabric surface is not completely covered with nanorods at 100-105℃, the nanorods are somewhat uneven in size at 110℃, the nanorods are dense and uniform in thickness at 115-120℃, and the nanorods gradually collapse at 125-130℃.

[0129] Example 3

[0130] The reaction time in step (4) of Example 1 was adjusted to 4, 5, 6, 7, 8, and 9 hours, while other steps remained the same as in Example 1, to obtain polyester fabric modified by lipase and titanium dioxide nanorods.

[0131] The obtained lipase and titanium dioxide nanorods were combined to modify polyester fabric, and the performance was tested. The test results are as follows: Figure 7 :

[0132] from Figure 7 It can be seen that as the growth time of titanium dioxide nanorods increases, the density of nanorods on the surface of the polyester fabric gradually increases, and the nanorods gradually grow while their diameter gradually thickens. However, starting from 8 hours, the nanorod structure begins to collapse, and the tips begin to thin. By 9 hours, the diameter of the nanorods begins to thin, and the fabric shows signs of damage.

[0133] Comparative Example 4

[0134] Step (1) of Example 1 is omitted, and nano-carbon dioxide rods are grown directly on the refined polyester fabric, with the specific parameters being consistent with those of Example 1.

[0135] The results showed that no rod-like structures appeared on the surface of the fabric without enzymatic reaction. This is because the surface of the fabric without enzymatic reaction has very few active groups, and the titanium sol has no active sites to attach to, so the nanorods cannot grow. Instead, they only form particulate matter on the fabric surface and cannot form rods. Specifically, as shown below... Figure 8 .

[0136] Comparative Example 5

[0137] The step (1) of Example 1 is adjusted to an alkaline treatment, as follows:

[0138] The refined polyester fabric was immersed in a 5 g / L NaOH solution at a bath ratio of 1:20, and then the accelerator hexadecyl ammonium bromide (content of 0.5 g / L) was added. The reaction was carried out at 96℃ for 0.5 h. After the reaction was completed, the fabric was taken out and neutralized with 0.5 mol hydrochloric acid, washed with deionized water, and dried at 105℃ to obtain the alkali-treated polyester fabric.

[0139] Everything else remained the same as in Example 1, resulting in a polyester fabric modified by a combination of titanium dioxide nanorods and alkali treatment.

[0140] The obtained polyester fabric was subjected to performance testing, and the test results are as follows:

[0141] Alkali treatment roughens the polyester surface by peeling it off, which severely damages the fabric's strength. After hydrothermal reaction, the fabric shows obvious surface damage, and after drying, it tears easily and has almost no mechanical properties. Specifically, for example... Figure 9 .

[0142] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A method for modifying polyester fabrics based on lipase and titanium dioxide nanorods, characterized in that, Includes the following steps: (1) Lipase treatment: The refined polyester fabric was immersed in a lipase solution, and then Tween 80 was added to carry out the reaction. After the reaction was completed, the fabric was removed, washed, and dried to obtain the lipase-treated polyester fabric. The bath ratio for lipase treatment was 1:20-50; the lipase solution was an aqueous solution of lipase with a concentration of 60-100 U / mL; the concentration of Tween 80 in the lipase solution was 1-3 g / L; the reaction was carried out at 50-70℃ for 12-36 h; and the lipase activity was 100-500 U / mg. (2) Titanium sol treatment: Tetrabutyl titanate, water, concentrated nitric acid, and anhydrous ethanol were mixed evenly to obtain a titanium sol solution. Lipase-treated polyester fabric was immersed in the titanium sol solution and then removed to obtain titanium sol-treated polyester fabric. The molar ratio of tetrabutyl titanate, water, concentrated nitric acid, and anhydrous ethanol was 1:1:0.1:9.

25. Mixing was performed by stirring at 500-1000 rpm for 1-2 hours. The bath ratio for titanium sol treatment was 1:20-50, the temperature was 20-30℃, and the treatment time was 12-36 hours. (3) Acid solution treatment: A titanium sol-treated polyester fabric was immersed in a hydrochloric acid solution for reaction. After the reaction was completed, the fabric was removed, washed, and dried to obtain the acid-treated polyester fabric. The reaction bath ratio was 1:20-50, the temperature was 50-80℃, and the time was 12-36h. The hydrochloric acid solution was an aqueous solution with a concentration of 0.1-0.5mol / L. (4) Growth of nano-titanium dioxide nanorods: Titanium source was added to a concentrated hydrochloric acid aqueous solution and mixed evenly to obtain a titanium dioxide nanorod growth solution. Then, an acid-treated polyester fabric was immersed in the titanium dioxide nanorod growth solution and reacted at 110-120℃ for 4-7 hours. After the reaction, the fabric was removed, washed, and dried to obtain a polyester fabric modified with lipase and titanium dioxide nanorods. The mass fraction of the titanium source in the concentrated hydrochloric acid aqueous solution was 1-5%. The titanium source was tetrabutyl titanate. The concentrated hydrochloric acid aqueous solution was obtained by mixing concentrated hydrochloric acid and water at a volume ratio of 1:1-3 and stirring at 500-1000 rpm for 10-30 minutes. The bath ratio of the reaction was 1:20-50.

2. The method according to claim 1, characterized in that, In step (1), the method for preparing the refined polyester fabric is as follows: The polyester fabric is placed in a solution of soap flakes and sodium carbonate for desizing, sizing, washing, drying, and equilibration in a constant temperature and humidity chamber to obtain a refined polyester fabric. In the soap flakes and sodium carbonate solution, the concentration of soap is 4-6 g / L, the concentration of sodium carbonate is 3-5 g / L, and the solvent is water. The bath ratio for desizing and simmering is 1:20-50, the temperature is 95-100℃, and the time is 20-40 minutes.

3. The method according to claim 1, characterized in that, In step (1), the washing process involves sequentially washing with sodium dodecyl sulfate, anhydrous ethanol, and water.

4. The method according to claim 1, characterized in that, In step (4), the reaction is carried out at 115-120℃.

5. The method according to claim 1, characterized in that, In step (4), the reaction takes 6-7 hours.

6. The lipase and titanium dioxide nanorod-modified polyester fabric prepared by the method according to any one of claims 1-5.

7. The application of the lipase and titanium dioxide nanorods combined modified polyester fabric as described in claim 6 in the textile field.

8. A textile product, characterized in that, It is prepared by using the lipase and titanium dioxide nanorods described in claim 6 to modify polyester fabric.

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