MOFs-mediated normal temperature and pressure dyeing and synergistically constructed anti-ultraviolet and self-cleaning polyester / cotton fabric and preparation method thereof

Abstract

The application relates to a MOFs-mediated normal-temperature and normal-pressure dyeing and synergic construction of anti-ultraviolet and self-cleaning polyester / cotton fabric and a preparation method thereof, and belongs to the technical field of fabric materials. The method for the MOFs-mediated normal-temperature and normal-pressure dyeing and synergic construction of anti-ultraviolet and self-cleaning polyester / cotton fabric comprises the following steps: S1, porous MOFs are in-situ grown on an oxidized polyester / cotton fabric to obtain a modified fabric; S2, normal-temperature and normal-pressure dyeing treatment is conducted on the modified fabric to obtain a dyed MOFs modified polyester / cotton fabric; and S3, PVDF is used to conduct coating treatment on the dyed MOFs modified polyester / cotton fabric to obtain an anti-ultraviolet and self-cleaning polyester / cotton fabric. Through the synchronous construction of controllable coordination of metal organic frameworks and micro-nano rough structures of fluorocarbon polymers, efficient and uniform dyeing of acid dyes on polyester / cotton two phases is realized without damaging the fiber strength, and the fabric is endowed with persistent anti-ultraviolet, high hydrophobicity and excellent self-cleaning performance.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of fabric, in particular to a MOFs-mediated normal-temperature and normal-pressure dyeing and synergistically constructed anti-ultraviolet and self-cleaning polyester / cotton fabric and a preparation method thereof. BACKGROUND

[0002] The polyester / cotton fabric has both polyester strength and cotton moisture absorption and air permeability, but is long-term limited in the dyeing and finishing link due to the difference in two-phase nature: PET (polyethylene terephthalate) is high-crystalline and hydrophobic, and has a high glass transition temperature, so traditional dyeing must be at a temperature of 125-135 DEG C and a steam pressure of 2 bar or above to force the disperse dye into the fiber interior; although cotton fiber can react with reactive or acid dyes at 60-80 DEG C, the temperature window is dislocated with that of polyester, forcing the factory to use the two-bath two-step route of "high-temperature and high-pressure dyeing of polyester -> cooling and dyeing of cotton", which consumes a large amount of steam, electricity and dyeing chemicals, and the temperature gradient and uneven tension easily cause color bleeding, color difference and fastness decline. Although normal-temperature and normal-pressure dyeing research reduces the temperature by using carriers, microcapsules or swelling agents, the dyeing rate is low, the fastness is poor, the residual toxicity is large, and the polyester / cotton blended system is still helpless. In terms of functional finishing, anti-ultraviolet relies on high-temperature baking of inorganic particles such as TiO2 and ZnO, and hydrophobicity / self-cleaning relies on secondary cross-linking of fluorosilane or PVDF (polyvinylidene fluoride) coating, which is independent in steps and repeated in equipment, and the cross-linking temperature often reaches 150 DEG C, which not only increases energy consumption but also causes dye thermal migration, resulting in hardening of hand feeling, decrease of moisture permeability and further deterioration of color fastness. The current situation of high energy consumption, high emission, multiple processes and single function makes the industry urgently need a green process that can complete uniform dyeing and integrate anti-ultraviolet, hydrophobic and self-cleaning functions under mild conditions.

[0003] The existing technology divides the functional modification into three independent paths: (1) depositing metal-organic framework UiO-66 on the surface of pure polyester by high-temperature solvothermal deposition, and then solidifying by fluorosilane at high temperature, only to obtain anti-ultraviolet and hydrophobic effects; (2) low-temperature dyeing of polyester at about 95 DEG C with phase change microcapsules and carriers, but it cannot consider the cotton component, and the fastness and uniformity are still poor; (3) high-temperature cross-linking of PVDF and nano-TiO2 coating to form an anti-ultraviolet super-hydrophobic layer, which increases the thickness and hardness, and dyeing must be additionally printed. All of the above three methods require heat treatment at 120-150 DEG C, and dyeing and functional finishing are completed in steps, and have not yet realized one-time dyeing and simultaneous endowment of durable anti-ultraviolet, hydrophobic and self-cleaning properties on polyester / cotton blended fabric under normal temperature and normal pressure.

[0004] The polyester / cotton blended fabric is prone to three pain points in actual use and dyeing and finishing process. Firstly, the molecular structure of polyester component is dense, and the conjugate system is insufficient, resulting in weak innate ultraviolet resistance. The fabric is rapidly photo-oxidized and degraded under long-term outdoor light, and the light aging phenomena such as discoloration, yellowing and mechanical strength drop occur, which seriously shortens the service life and reduces the aesthetic value. Secondly, the polyester and cotton fibers differ significantly in key dyeing parameters such as polarity, crystallinity and glass transition temperature. The traditional process has to rely on high temperature above 130 ℃ and high pressure above 2 bar, which not only causes large consumption of steam, electricity and dyeing chemicals, but also easily causes quality defects such as color mottle, color difference and fastness reduction due to uneven temperature, tension or additive distribution, which is difficult to meet the strict requirements of continuous mass production on uniformity and reproducibility. Thirdly, the conventional finishing technology can usually only give the fabric single function. If the anti-ultraviolet, hydrophobic and self-cleaning properties are required at the same time, multi-step composite processing is needed, which not only has a long process, but also doubles the amount of chemicals, and the compatibility between each functional layer is poor and the durability is low, further increasing the environmental load.

[0005] In summary, the existing technology has the following defects: 1. High temperature and high pressure dependence: The rigid dependence of the existing technology on dyeing temperature and pressure makes the polyester chain segment must be fully swollen at high temperature and high pressure, resulting in high energy consumption of the whole machine, large equipment investment, and narrow process window, which is prone to uneven dyeing due to temperature fluctuations. 2. Poor dyeing uniformity: The affinity of polyester / cotton heterogeneous fibers for dyes and the difference in swelling temperature are significant, and the existing method cannot achieve uniform coloring in the same bath, color mottle and color difference occur frequently, and the dyeing reproducibility and fastness are difficult to meet the requirements of high-end fabrics. 3. Long and fragmented process: The traditional route separates dyeing, anti-ultraviolet and hydrophobic finishing into multiple independent steps, which has a long process, additive stacking, and waste water and carbon emissions are doubled, while multiple drying and baking exacerbate fiber damage. 4. Weak functional durability: The conventional finishing coating or surface modification layer has weak adhesion to the fiber, which quickly fails after washing and rubbing, resulting in rapid degradation of anti-ultraviolet, hydrophobic and self-cleaning properties, which is difficult to meet the long-term outdoor use durability requirements. SUMMARY

[0006] Therefore, the present application provides a MOFs mediated normal temperature and pressure dyeing and cooperatively constructed anti-ultraviolet and self-cleaning polyester / cotton fabric and its preparation method, aiming to develop a normal temperature and pressure modification-dyeing integrated process based on the synergistic effect of UiO-66 and PVDF, through the controlled coordination of metal organic framework and the synchronous construction of fluorocarbon polymer micro-nano rough structure, realizing the efficient and uniform dyeing of acid dyes on polyester / cotton two phases without damaging the fiber strength, and giving the fabric persistent anti-ultraviolet, high hydrophobic and excellent self-cleaning properties, thereby completely breaking through the limitations of existing technology in high pollution, high energy consumption and multi-functional integration in a green, low energy consumption and short process way, which can effectively overcome the defects of the above existing technology.

[0007] The first aspect of the application provides a method for mediating normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric by MOFs, comprising the following steps:

[0008] S1, growing porous MOFs in situ on the oxidized polyester / cotton fabric to obtain a modified fabric;

[0009] S2, performing normal temperature and pressure dyeing treatment on the modified fabric to obtain a dyed MOFs modified polyester / cotton fabric;

[0010] S3, performing coating treatment on the dyed MOFs modified polyester / cotton fabric with PVDF to obtain an anti-ultraviolet and self-cleaning polyester / cotton fabric.

[0011] Preferably, the step S1 specifically comprises the following steps:

[0012] S101, preparing a metal precursor solution: dissolving ZrOCl2·8H2O in a mixed solution of deionized water and acetic acid, generating Zr6O4(OH)4(CH3COO) after reacting at a temperature of 75°C for 2 hours 12 to obtain a metal precursor solution;

[0013] S102, preparing a ligand precursor solution: first adding terephthalic acid and NaOH into deionized water, stirring at a temperature of 60°C for 10 min until becoming a clear solution, and then cooling to room temperature to obtain a ligand precursor solution;

[0014] S103, transferring the oxidized polyester / cotton fabric into the metal precursor solution, reacting at a temperature of 75°C for 2 hours, then adding the ligand precursor solution drop by drop, uniformly mixing, and then reacting at room temperature for 2 hours, taking out the oxidized polyester / cotton fabric, washing with deionized water and ethanol each for 2 times, and drying at a temperature of 60°C to collect.

[0015] Specifically, the conventional solvothermal triggering is changed to room temperature ultrasonic assistance, microwave assistance or light-induced free radical polymerization, which promotes the rapid nucleation of MOF (metal organic framework) on the fiber surface, shortens the reaction time and further reduces the energy consumption.

[0016] Specifically, ethanol-water, ethyl lactate or deep eutectic solvent (DES) is used to replace toxic solvents such as DMF (N,N-dimethylformamide) to dissolve the precursors and maintain the nucleation kinetics of MOF at normal temperature and pressure, realizing VOC (volatile organic compound) free emission in the whole process.

[0017] Preferably, in the step S103, the specific preparation process of the oxidized polyester / cotton fabric is as follows:

[0018] The terylene / cotton fabric is cut into 6 cm x 6 cm, then transferred to a NaOH solution with a mass fraction of 10-30%, and reacted at a temperature of 70-80 ℃ for 0.5-1 hour, then washed with distilled water until the pH value is neutral, and dried at a temperature of 60 ℃; then 1 M sodium chloroacetate is dissolved in a 5% sodium hydroxide solution, and the dried terylene / cotton fabric is immersed, stirred and reacted at room temperature for 1 h, washed with deionized water to remove residual reagents, and dried at room temperature overnight to obtain the oxidized terylene / cotton fabric.

[0019] Preferably, the step S2 specifically comprises the following steps:

[0020] The modified fabric is cut into 3 cm x 3 cm, and the modified fabric is dyed with reactive blue dye, direct blue dye, disperse blue dye and weak acid red dye respectively, with a bath ratio of 1:50, and 1 g / L of NNO (sodium methylene bisnaphthalene sulfonate) is added to the dye bath when using disperse blue dye for dyeing, the dyeing time is 4 h, and the dyeing is carried out at room temperature and normal pressure using a water bath shaker, after dyeing, the fabric is washed with deionized water to remove the surface color, and finally the washed fabric is dried in an oven at 100 ℃, to obtain the dyed MOFs modified terylene / cotton fabric, wherein the MOFs are selected from one of UiO-66, UiO-67, MIL-140C, MIL-101, MIL-53, MOF-801, MOF-808, ZIF-8. Specifically, the MOFs are selected from one of UiO-66, UiO-67, MIL-140C, MIL-101(Al), MIL-53(Al), MOF-801(Zr), MOF-808(Zr), ZIF-8(Zn). Specifically, the larger pore size or adjustable functional groups are used to realize dye release and ultraviolet absorption, and hydrogen bonding / coordination anchoring is formed between the surface carboxyl, hydroxyl or amino and PVDF.

[0021] Preferably, the reactive blue is selected from one of reactive blue K-2R, reactive blue P-3R, reactive brilliant blue KN-R, reactive blue BRF.

[0022] Preferably, the direct blue dye is selected from one of direct blue B2-2L, direct blue 86, direct blue 15.

[0023] Preferably, the disperse blue dye is selected from at least one of disperse turquoise blue S-GL, disperse blue 354, disperse blue 366, disperse yellow 134, disperse blue PUD-B, disperse blue 183.

[0024] Preferably, the weak acid red dye is selected from one of weak acid red B, weak acid red A-2BF, weak acid red N-5BL, weak acid brilliant red B.

[0025] Specifically, by adjusting pH and electrolyte concentration, active dyes, direct dyes, cationic dyes or disperse / active-bath type composite dyes form coordination or electrostatic adsorption with the open metal sites of different MOFs to complete the dyeing at normal temperature and pressure.

[0026] Preferably, the step S3 specifically comprises the following steps:

[0027] The dyed MOFs modified polyester / cotton fabric is coated with 3-8% wt polyvinylidene fluoride film and is cycle-dried at 100 ℃ and 130 ℃ until the film completely covers the surface of the polyester / cotton fabric. Specifically, PVDF is replaced by PVDF-HFP (polyvinylidene fluoride-hexafluoropropylene), PVDF-TrFE (polyvinylidene fluoride-trifluoroethylene), PTFE (polytetrafluoroethylene) emulsion, FEP (fluorinated ethylene propylene copolymer) emulsion or fluorinated polyurethane to construct a low-surface-energy hydrophobic layer through the same low-temperature phase change film-forming mechanism, and a fluorine-containing acrylic ester copolymer can be further introduced to improve flexibility.

[0028] The second aspect of the present application also provides an anti-ultraviolet, self-cleaning polyester / cotton fabric prepared by the above method.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] 1. In view of the defects of the prior art such as high temperature and high pressure, process fragmentation, uneven dyeing, insufficient durability and deteriorated hand feeling, the present application takes the microstructure difference of polyester / cotton fibers as the breakthrough point, and uses the nanoscale porous framework formed by the in-situ growth of Zr-oxo nodes and carboxyl ligands on the surface of the fibers at room temperature: the pores have reversible adsorption-release effect on acidic dyes, allowing the dyes to diffuse and uniformly fix between the two fibers with different glass transition temperatures, thereby breaking the dependence on high temperature and high pressure; at the same time, the strong ultraviolet absorption band of UiO-66 and the energy level transition of Zr-oxo clusters synergistically dissipate ultraviolet energy, giving the fabric a durable anti-aging barrier. On this basis, the PVDF low-surface-energy segment is anchored to the open metal sites of UiO-66 through hydrogen bonding, constructing a micro-nano dual rough structure, and a stable hydrophobic layer can be formed at room temperature; the thickness of the layer is only tens of nanometers, which does not block the fiber pores, and the air permeability and hand feeling are maintained. The three components synergistically realize the one-step completion of dyeing, anti-ultraviolet, hydrophobicity and self-cleaning multifunctional integration at room temperature and pressure, the process chain is shortened, the chemicals and energy consumption are significantly reduced, and the functional layer is firmly locked in a chemical bond-physical nesting dual mode, which is washable and wear-resistant, and still maintains high color fastness, high UPF (ultraviolet protection factor) and high contact angle during long-term outdoor use, completely breaking through the bottleneck of the prior art.

[0031] 2. This application's one-step system under ambient temperature and pressure: This application compresses the three originally independent high-temperature and high-pressure steps of dyeing, nucleation, and encapsulation into a single, gentle water bath process. Through the reversible adsorption-slow release of acidic dyes via the UiO-66 channels and the reversible coordination of dyes with zirconium nodes, an integrated "dyeing-functionality" microenvironment is formed on the fiber surface, significantly reducing energy consumption and shortening the process.

[0032] 3. The bifunctional UiO-66 framework of this application: The Zr-oxo node has a reversible adsorption-slow release effect on dye molecules, which enables polyester and cotton to be dyed uniformly within the same temperature gradient; its ligand-metal charge transfer band covers the ultraviolet region, directly absorbs ultraviolet light and converts it into harmless heat energy, avoiding the agglomeration and deterioration of hand feel caused by the addition of inorganic nanoparticles.

[0033] 4. PVDF micro-nano hydrophobic layer of this application: PVDF segments are anchored to the UiO-66 surface through hydrogen bonds, inducing the directional alignment of the β phase crystal region to form ultrathin nanofolds; this structure constructs a stable Cassie-Baxter state (also known as Cassie state for short) while maintaining interfiber porosity, and still maintains high hydrophobic angle and good air permeability after water washing.

[0034] 5. The four-level continuous interface of this application: fiber-dye-UiO-66-PVDF form a continuous interface through chemical bonds and physical nesting, and the overall structure cannot be separated; the absence of any level will lead to uneven dyeing, reduced UV shielding or hydrophobic failure, becoming an independent product form and protected object. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of this application or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0036] Figure 1 The XRD (X-ray powder diffraction) curves of UiO-66, polyester / cotton base fabric, and UiO-66 modified polyester / cotton fabric in Example 1 are shown.

[0037] Figure 2 The images show the FT-IR (infrared spectra) of the UiO-66 modified polyester / cotton fabric and the original polyester / cotton fabric in Example 1.

[0038] Figure 3 SEM images of polyester / cotton fabrics before and after UiO-66 modification; Figure 3 (a) is an SEM (scanning electron microscope) image of untreated polyester / cotton fabric; Figure 3 (b) andFigure 3 (c) is a SEM image of the polyester / cotton fabric modified with UiO-66 in Example 1;

[0039] Figure 4 The water contact angles are those of the polyester-cotton base fabric and those of Examples 1, 4, and 5 after being modified with UiO-66 once, twice, and three times, and after being coated with PVDF.

[0040] Figure 5 The hydrophobic durability of polyester / cotton fabrics before and after UiO-66 and PVDF modification is shown in the figure. Figure 5 In the figure, (a) represents the water contact angle of the polyester-cotton base fabric; Figure 5 In Example 1, (b) represents the contact angle of the UiO-66 modified fabric after PVDF coating.

[0041] Figure 6 The graph shows the UPF value changes of polyester / cotton fabrics modified with UiO-66 in Example 1.

[0042] Figure 7 The graph shows the changes in dye uptake of different dyes on polyester / cotton fabrics before and after UiO-66 modification. Figure 7 (a) in the diagram is a dyeing pattern for polyester / cotton raw fabric. Figure 7 (b) in the figure is a dyeing diagram of the fabric modified with UiO-66 in Example 1;

[0043] Figure 8 The diagram shows the self-cleaning properties of polyester / cotton fabrics before and after modification with UiO-66 and PVDF. Figure 8 (a) in the image shows a stain that came into contact with the polyester / cotton fabric. Figure 8 (b) in Example 1 shows the contact stains on the polyester / cotton fabric after UiO-66 modification. Figure 8 (c) in the figure represents a PVDF coating on the fabric surface. Figure 8 (d1, d2, d3, d4) and Figure 8 (e1, e2, e3, e4) represent the self-cleaning process of polyester / cotton fabrics. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0045] Unless otherwise specified, the experimental methods used in the embodiments of this application are all conventional methods.

[0046] In the following examples, all raw materials can be prepared by commercial or conventional methods, unless otherwise specified.

[0047] It should be noted that the MOFs are selected from one of UiO-66, UiO-67, MIL-140C, MIL-101 (Al), MIL-53 (Al), MOF-801 (Zr), MOF-808 (Zr), ZIF-8 (Zn). Among them, the former represents a class of MOF materials, and the one in the brackets is one of the MOFs in this class, such as MIL-101 (Al) and MIL-101 (Cr) both belong to the MIL-101 series, the three-dimensional structure and the metal ligand coordination mode are consistent, the only difference is that the two metal ions are different, one is Al, and one is Cr.

[0048] Example 1

[0049] A MOF-based fabric is constructed by in-situ self-assembly of porous MOFs and polyester / cotton fabric, then dyeing and fixing are completed at normal temperature and pressure, and a micro-nano rough hydrophobic self-sealing surface treatment is performed on the surface by PVDF coating. The method of this embodiment for MOF-mediated normal temperature and pressure dyeing and cooperatively constructing anti-ultraviolet and self-cleaning polyester / cotton fabric comprises the following steps:

[0050] 1. Polyester / cotton fabric activation: Place a 6 cm x 6 cm polyester / cotton fabric in a 12 mL solution of 15% NaOH, react at 70°C for 1 hour, then wash with distilled water until the pH is neutral, and dry in an oven at 60°C. Then dissolve 1 M sodium chloroacetate in 40 mL of 5% NaOH solution, immerse the dried polyester / cotton fabric in the solution, and stir at room temperature for 1 hour. Finally, wash with deionized water to remove residual reagents, and dry at room temperature overnight.

[0051] 2. Synthesis of MOF-based fabric: ① Prepare a metal precursor solution: dissolve ZrOCl2·8H2O (1.3104 g, 1 mmol) in a mixture of deionized water (28.8 mL) and acetic acid (4.8 mL), and react at 75°C for 2 hours to generate Zr6O4(OH)4(CH3COO) 12 . ② Prepare a ligand precursor solution: first add terephthalic acid (0.6644 g, 1 mmol) and NaOH (0.32 g, 2 mmol) to 20 mL of deionized water, stir at 60°C for 10 min until it becomes a clear solution, then cool to room temperature. ③ Transfer the activated polyester / cotton fabric to the metal precursor solution and react at 75°C for 2 hours. ④ Add the ligand precursor solution dropwise to ③, mix well, and react at room temperature for 2 hours. ⑤ Take out the above fabric, wash it in deionized water and ethanol for 2 times respectively, and dry at 60°C to collect.

[0052] 3. MOF-based fabric dyeing and fixing: MOF-based fabric is cut into 3 cm x 3 cm, and four dyes are used respectively: reactive blue K-2R, direct blue B2-2L, disperse turquoise blue S-GL and weak acid red B, bath ratio 1:50, disperse blue dyeing needs to add dispersing agent NNO (1 g / L) in the dye bath, the dyeing time is 4 h, and the dyeing is carried out at room temperature and normal pressure by using a water bath shaker. After dyeing, the fabric surface is washed with deionized water, and finally the washed fabric is dried in an oven at 100 ℃.

[0053] 4. Coating treatment: the dyed MOF-based fabric is coated with polyvinylidene fluoride (5% wt solution) and dried at 100 ℃ (1 min) and 130 ℃ (2 min) in a cycle until the film completely covers the surface of the polyester / cotton fabric.

[0054] Example 2

[0055] The method of MOFs-mediated room temperature and normal pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in this example can refer to Example 1, except that the 15% NaOH solution by mass fraction in the polyester / cotton fabric activation is replaced by 20% NaOH solution by mass fraction at 70 ℃ for 0.5 h.

[0056] Example 3

[0057] The method of MOFs-mediated room temperature and normal pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in this example can refer to Example 1, except that the 15% NaOH solution by mass fraction in the polyester / cotton fabric activation is replaced by 10% NaOH solution by mass fraction at 80 ℃ for 1 h.

[0058] Example 4

[0059] The method of MOFs-mediated room temperature and normal pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in this example can refer to Example 1, except that the MOF-based fabric obtained in Example 1 is placed in the metal precursor solution and the ligand precursor solution again for the second modification according to the steps.

[0060] Example 5

[0061] The method of MOFs-mediated room temperature and normal pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in this example can refer to Example 1, except that the MOF-based fabric obtained in Example 4 is placed in the metal precursor solution and the ligand precursor solution again for the third modification according to the steps.

[0062] Example 6

[0063] The method for MOFs-mediated normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in the embodiment can refer to Embodiment 1, except that UiO-66 is replaced by UiO-67, that is, the ligand terephthalic acid is replaced by 4,4'-biphenyldicarboxylic acid for preparation (the preparation method refers to the prior art, for example: the synthesis schemes of UiO-66 and UiO-67 have been reported in foreign language documents, the main difference between them is that the ligands are different; but in the embodiment, the synthesis temperature of the two materials is adjusted according to the system of the application, Journal of Separation Science 41.22 (2018): 4149-4158).

[0064] Embodiment 7

[0065] The method for MOFs-mediated normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in the embodiment can refer to Embodiment 1, except that UiO-66 is replaced by MIL-140C, that is, the ligand terephthalic acid is replaced by 2,5-dihydroxyterephthalic acid for preparation (the preparation method refers to the prior art, for example: Chemistry–A European Journal 25.59 (2019): 13598-13608).

[0066] Embodiment 8

[0067] The method for MOFs-mediated normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in the embodiment can refer to Embodiment 1, except that UiO-66 is replaced by MIL-101 (Al), that is, ZrOCl2·8H2O is replaced by AlCl3·6H2O for preparation (the preparation method refers to the prior art, for example: Molecular Catalysis 482 (2020): 110635).

[0068] Embodiment 9

[0069] The method for MOFs-mediated normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in the embodiment can refer to Embodiment 1, except that active blue K-2R in the four dyes is replaced by active blue P-3R, active brilliant blue KN-R or active blue BRF.

[0070] Embodiment 10

[0071] The method for MOFs-mediated normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in the embodiment can refer to Embodiment 1, except that direct blue B2-2L in the four dyes is replaced by direct blue 86 or direct blue 15.

[0072] Embodiment 11

[0073] The method for MOFs-mediated normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in the embodiment can refer to Embodiment 1, except that weak acid red B in the four dyes is replaced by weak acid red A-2BF, weak acid red N-5BL or weak acid brilliant red B.

[0074] Embodiment 12

[0075] The method for MOFs-mediated normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in the embodiment can refer to Embodiment 1, except that weak acid red B in the four dyes is replaced by weak acid red A-2BF, weak acid red N-5BL or weak acid brilliant red B.

[0076] Embodiment 13

[0077] The method for MOFs-mediated normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in the embodiment can refer to Embodiment 1, except that, in the coating treatment, polyvinylidene fluoride (5% wt solution) coating is replaced by polyvinylidene fluoride (3% wt solution) coating, which is cyclically dried at 100 °C (1 minute) and 130 °C (1 minute).

[0078] Embodiment 14

[0079] The method for MOFs-mediated normal temperature and pressure dyeing and synergistically constructing anti-ultraviolet and self-cleaning polyester / cotton fabric provided in the embodiment can refer to Embodiment 1, except that, in the coating treatment, polyvinylidene fluoride (5% wt solution) coating is replaced by polyvinylidene fluoride (8% wt solution) coating, which is cyclically dried at 100 °C (3 minutes) and 130 °C (2 minutes).

[0080] Test Example

[0081] 1、as Figure 1As shown, XRD characterization confirmed the successful self-growth of UiO-66 onto the surface of polyester / cotton fibers. The introduction of UiO-66 resulted in characteristic peaks at 7.3°, 17.2°, and 27.5° in the polyester / cotton blended fabric, which matched the simulated peak pattern of UiO-66 powder, confirming the presence of UiO-66 on the polyester / cotton fibers. Furthermore, observation of the peak shape changes before and after modification revealed a decrease in the intensity of the crystallization peak in the UiO-66-modified polyester / cotton fabric (UiO-66 / TC (polyester / cotton fabric)). The peak at 27.5° in the modified fabric shifted backward compared to the UiO-66 powder peak, primarily attributed to the reduced substrate crystallinity due to the interaction between UiO-66 covering the fabric surface and the interface. This further confirms the successful growth of UiO-66 on the polyester / cotton fabric surface through coordination modification.

[0082] 2. For example Figure 2 As shown, to further demonstrate the successful grafting of UiO-66 onto polyester / cotton fabrics, infrared spectroscopy was used to analyze the types of chemical bonds and functional groups in the polyester / cotton fabrics before and after UiO-66 modification. The results were obtained at 1713, 2361, and 777 cm⁻¹. -1 The presence of characteristic peaks for UiO-66 at three locations indicates that UiO-66 has been successfully modified onto polyester / cotton fabrics. Simultaneously, TC and UiO-66 / TC are both at 3337, 1319, 1165, and 1112 cm⁻¹. -1 Characteristic peaks appear at 1713 and 1640 cm⁻¹, corresponding to the asymmetric stretching peaks of C=O, CCO, and OCC groups in polyester / cotton fabrics, as well as the CH rocking vibration of the benzene ring. -1 The peak at 2361 cm⁻¹ is considered to be the OCO asymmetric and symmetric stretching peak in the H₂BDC ligand, while the C=O peak in the carboxylic acid of UiO-66 / TC is at 2361 cm⁻¹. -1 The decrease in intensity at this point indicates that the ligand has coordinated with the metal precursor. At 777 cm⁻¹ -1 The peak at the position is considered to be Zr-O stretching in UiO-66. This is a characteristic peak produced by the introduction of Zr-O, indicating that Zr clusters are grafted onto the carboxyl side chains of the fiber. This also confirms that UiO-66 has successfully modified polyester / cotton fabrics.

[0083] 3. The in-situ growth of UiO-66 on the surface of polyester / cotton fibers was characterized by SEM testing. Figure 3 In (a), it is clear that the surface of the unmodified fiber is relatively smooth, while the surface of the UiO-66 modified polyester / cotton fiber has many fine, irregular crystalline particles, such as... Figure 3 As shown in (b) above. Further observation at the 5 μm level revealed that the polyester / cotton fiber surface exhibited etched and pitted surfaces, as shown in [image 1]. Figure 3(c) shown in FIG. 4, in contrast to the flat and smooth surface of the untreated polyester / cotton fabric, the etched and pitted surface is due to the fabric substrate in the activation process OH - The result shows that the fiber micro-morphology and surface structure are successfully changed by the modification of UiO-66, and also shows that the UiO-66 is successfully grown on the surface of the polyester / cotton fabric.

[0084] 4. The water contact angle of the modified polyester / cotton fabric was measured by a contact angle measuring instrument. From Figure 4 It can be seen from FIG. 5 that the water contact angle of the polyester / cotton fabric measured after 1, 2, and 3 modifications respectively shows an obvious increasing trend, and the contact angle of the UiO-66 / TC-3 composite fabric finally reaches 129.3°. After further modification by PVDF coating, the contact angle of the UiO-66 / TC-3 / PVDF composite fabric increases significantly, reaching 146.7°. This phenomenon is attributed to the fact that after the growth of UiO-66, many small crystal particles are distributed on the surface of the fiber, and with the increase of the modification times, the number of small particles also increases, so the roughness of the fiber surface gradually increases, and therefore the contact angle of the composite fabric also gradually increases; after the coating of PVDF, not only can the UiO-66 on the surface of the fabric be protected from falling off, but also PVDF can provide low surface energy and build a micro-nano double rough structure.

[0085] 5. The durability of the water contact angle of the modified and unmodified polyester / cotton fabric was characterized by a contact angle measuring instrument. From Figure 5 It can be seen from FIG. 6 that the contact angle of the polyester / cotton fabric is 71.31° when the water is just dropped, and the water droplet will be quickly absorbed into the fabric after 5 seconds, which indicates that the hydrophobicity of the polyester / cotton fabric is poor. The contact angle of the polyester / cotton fabric modified by UiO-66 is greater than 90°, and with the increase of the modification times, the contact angle also shows a gradually increasing trend. In order to make the hydrophobic effect of the polyester / cotton fabric modified by UiO-66 have better stability, PVDF is used to coat the dyed UiO-66 modified polyester / cotton fabric (UiO-66 / TC-3 / PVDF), and the test result is shown in (b) of FIG. 6. It can be seen that the water contact angle of UiO-66 / TC-3 / PVDF is maintained at more than 130°, which indicates that the polymer coating can improve the durability of the water contact angle of the fabric, and after 15 minutes of testing, the change of the contact angle of the water droplet on the surface of the fabric is less than 15° compared with the contact angle at 0 minutes, which also indicates that the hydrophobic effect of the fabric after the coating modification by PVDF has good durability. Figure 5

[0086] 6. The anti-ultraviolet performance of the modified and unmodified polyester / cotton fabric was tested by an anti-ultraviolet tester. From Figure 6 ​It can be seen that after three modifications, UiO-66 achieves effective absorption of ultraviolet rays on the surface of polyester / cotton fabrics. Moreover, after PVDF coating treatment, the UPF value can reach 476.1. This effect is mainly attributed to the fact that the modification of UiO-66 enhances the ultraviolet protection performance of polyester / cotton fabrics, and the PVDF coating also significantly improves the UPF value and achieves very good ultraviolet protection performance.

[0087] 7. The UiO-66-modified polyester / cotton fibers can improve dye adsorption performance through the formation of hydrogen bonds or coordinate bonds with dye molecules via the introduced carboxylic acid groups, as well as the high specific surface area of ​​UiO-66, thereby improving dyeing uniformity and color fastness. From Figure 7 It can be seen that the unmodified polyester / cotton fabric, when dyed under normal temperature and pressure conditions, produces a lighter color. This phenomenon indicates that under normal temperature and pressure conditions, the unmodified polyester / cotton fabric has a relatively weak adsorption capacity for dyes, resulting in a shallower dyeing depth. Conversely, under the same conditions, the UiO-66-modified polyester / cotton fabric produces a darker color after dyeing. This color difference can be attributed to the stronger adsorption properties of UiO-66 after modification, which allows the polyester / cotton fabric to adsorb dyes under normal temperature and pressure conditions.

[0088] 8. To further investigate the self-cleaning properties of UiO-66-modified polyester / cotton fabrics, self-cleaning performance tests were conducted on the modified polyester / cotton fabrics, such as... Figure 8 As shown. To simulate the situation where polyester / cotton fabric surfaces come into contact with contaminants during actual use, four contaminants will be used for testing: dye liquor, milk, cooking oil, and coffee. The contaminants will be simulated as being freely dripped onto the fabric surface. Figure 8 As shown in (a), when contaminants are dropped onto the surface of the polyester / cotton base fabric and remain there for 30 seconds, the contaminants are absorbed into the polyester / cotton fabric. Under the same conditions, when contaminants are dropped onto the surface of the UiO-66 modified polyester / cotton fabric and held for 30 seconds, each contaminant does not wet the composite fabric and maintains a large contact angle on the fabric surface, appearing as droplets. Figure 8 (b)); Meanwhile, when polyester / cotton fabrics are modified with UiO-66 and PVDF (UiO-66 / TC-3 / PVDF), their self-cleaning properties are greatly improved. Figure 8 (d1, d2, d3, d4) and Figure 8(e1, e2, e3, e4) in the figure are self-cleaning test processes of fabric using dyes and edible oil. It can be clearly seen from the figure that after the PVDF coating, the pollutants will directly roll off from the surface of the fabric without leaving any residual stains. This phenomenon confirms that the modification of UiO-66 and the coating of PVDF have high hydrophobicity and oleophobicity, and show good self-cleaning performance.

[0089] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for part or all of the technical features; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for MOFs mediated dyeing at room temperature and pressure and synergistically building up anti-UV, self-cleaning polyester / cotton fabric, characterized in that, It comprises the following steps: S1, porous MOFs are in-situ grown on the oxidized polyester / cotton fabric to obtain a modified fabric; S2, the modified fabric is subjected to normal temperature and pressure dyeing treatment to obtain a dyed MOFs modified polyester / cotton fabric; S3, the dyed MOFs modified polyester / cotton fabric is subjected to coating treatment with PVDF to obtain an ultraviolet-resistant and self-cleaning polyester / cotton fabric; The step S2 specifically comprises the following steps: The modified fabric is cut into 3 cm*3 cm, and the modified fabric is dyed with reactive blue dye, direct blue dye, disperse blue dye and weak acid red dye respectively, with a bath ratio of 1:50; when disperse blue dye is used for dyeing, 1 g / L of dispersing agent NNO needs to be added to the dye bath; the dyeing time is 4 h; the dyeing is carried out at normal temperature and pressure by using a water bath shaker; after dyeing, the fabric surface is washed with deionized water to remove the floating color; finally, the washed fabric is dried in an oven at 100 DEG C to obtain a dyed MOFs modified polyester / cotton fabric, wherein the MOFs are selected from one of UiO-66, UiO-67, MIL-140C, MIL-101, MIL-53, MOF-801, MOF-808 and ZIF-8.

2. The method for MOFs mediated dyeing at room temperature and pressure and synergistically building anti-ultraviolet, self-cleaning polyester / cotton fabric according to claim 1, characterized in that, The step S1 specifically comprises the following steps: S101, preparing a metal precursor solution: dissolving ZrOCl2·8H2O in a mixed solution of deionized water and acetic acid, and generating Zr6O4(OH)4(CH3COO) after reacting for 2 hours at a temperature of 75°C to obtain a metal precursor solution; 12 ​ S102, preparing a ligand precursor solution: first, terephthalic acid and NaOH are added to deionized water, stirred at 60 DEG C for 10 min until a clear solution is obtained, then cooled to room temperature to obtain a ligand precursor solution; S103, transferring the oxidized polyester / cotton fabric to the metal precursor solution, reacting at 75 DEG C for 2 hours, then adding the ligand precursor solution drop by drop, mixing uniformly and reacting at room temperature for 2 hours, then taking out the oxidized polyester / cotton fabric, washing with deionized water and ethanol for 2 times respectively, drying at 60 DEG C and collecting.

3. The method for MOFs mediated dyeing at room temperature and pressure and synergistically building up anti-UV, self-cleaning polyester / cotton fabric according to claim 2, characterized in that, In step S103, the specific preparation process of the oxidized polyester / cotton fabric is as follows: The polyester / cotton fabric is cut into 6 cm*6 cm, then transferred to a NaOH solution with a mass fraction of 10-30%, reacted at 70-80 DEG C for 0.5-1 hour, then washed with distilled water until the pH value is neutral, and dried at 60 DEG C; then 1 M sodium chloroacetate is dissolved in a 5% sodium hydroxide solution, the dried polyester / cotton fabric is immersed, stirred at room temperature for 1 h, washed with deionized water to remove residual reagents, and dried at room temperature overnight to obtain the oxidized polyester / cotton fabric.

4. The method for MOFs mediated dyeing at room temperature and pressure and synergistically building up anti-UV, self-cleaning polyester / cotton fabric according to claim 1, characterized in that, The reactive blue dye is selected from one of reactive blue K-2R, reactive blue P-3R, reactive brilliant blue KN-R and reactive blue BRF.

5. The method for MOFs mediated dyeing at room temperature and pressure and synergistically building up anti-UV, self-cleaning polyester / cotton fabric according to claim 1, characterized in that, The direct blue dye is selected from one of direct blue B2-2L, direct blue 86 and direct blue 15.

6. The method for MOFs mediated dyeing at room temperature and pressure and synergistically building up anti-UV, self-cleaning polyester / cotton fabric according to claim 1, characterized in that, The disperse blue dye is selected from at least one of disperse turquoise blue S-GL, disperse blue 354, disperse blue 366, disperse yellow 134, disperse blue PUD-B and disperse blue 183.

7. The method for MOFs mediated dyeing at room temperature and pressure and synergistically building up anti-UV, self-cleaning polyester / cotton fabric according to claim 1, characterized in that, The weak acid red dye is selected from one of weak acid red B, weak acid red A-2BF, weak acid red N-5BL and weak acid brilliant red B.

8. The method for MOFs mediated dyeing at room temperature and pressure and synergistically building up anti-UV, self-cleaning polyester / cotton fabric according to claim 1, characterized in that, The step S3 specifically comprises the following steps: The dyed MOFs modified polyester / cotton fabric is coated with 3-8% wt polyvinylidene fluoride film and is dried at 100 °C and 130 °C temperature conditions in cycles until the film completely covers the surface of the polyester / cotton fabric.

9. Anti-UV, self-cleaning polyester / cotton fabric, characterized in that it comprises a mixture of a UV absorber and a self-cleaning agent. The anti-ultraviolet, self-cleaning polyester / cotton fabric prepared by the method of any one of claims 1-8.

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