Ecological green fabric degradation process
By constructing a cross-linked hydrophobic shell in the blended fabric, the problems of stability during use and efficient degradation after disposal are solved, ensuring the whiteness and strength of the fabric and achieving stable adhesion and efficient degradation of functional components.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 福建恒捷实业有限公司
- Filing Date
- 2026-01-22
- Publication Date
- 2026-04-21
Smart Images
Figure SMS_9
Abstract
Description
Technical Field
[0001] This invention relates to the field of fabric degradation, specifically to an eco-friendly fabric degradation process. Background Technology
[0002] With the deep integration of the textile industry and environmental protection concepts, polyester and cotton blended fabrics have occupied a large share of the clothing market because they combine the strength of synthetic fibers with the comfort of natural fibers. However, the disposal of these blended fabrics after disposal is becoming increasingly prominent, especially since the polyester component has an extremely long degradation cycle in the natural environment, which puts lasting pressure on the ecological environment.
[0003] Currently, the industry mainly relies on physical crushing, landfilling, or simple chemical solvent soaking for the degradation treatment of blended fabrics. In practical applications, technicians usually need to collect waste fabrics and place them in a specific degradation solution for treatment, and regularly record the degradation status and weight loss of the fabrics. However, traditional degradation methods and monitoring methods face many challenges in actual operation. In the current technology, the auxiliary degradation components added to fabrics are easily lost during wearing and washing due to the lack of a stable physical barrier. This results in insufficient core degradation momentum and an abnormally sharp drop in degradation efficiency when the fabric enters the degradation stage after disposal. Existing modification treatments often lead to obvious color changes in the fabric during storage and use, such as yellowing or significant fluctuations in whiteness index, which seriously affects the product's performance and aesthetics. In addition, due to the lack of effective interfacial bonding methods, the adhesion of functional components to the fiber surface is extremely poor. After several standard washes, the strength retention rate and functional durability of the fabric cannot meet the expected standards, making it difficult to avoid the risk of degradation and functional failure caused by these factors. Therefore, how to achieve high stability of blended fabrics during use and efficient degradation after disposal, while maintaining the whiteness and strength of the fabric, has become an urgent problem to be solved in this field.
[0004] The information disclosed in the background section above is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention
[0005] The purpose of this invention is to provide an eco-friendly fabric degradation process to solve the problems mentioned in the background art.
[0006] The technical solution of the present invention includes the following steps: Step (1): In a reactor equipped with a mechanical stirrer, a condenser, and a nitrogen protection device, add anhydrous N,N-dimethylformamide to dissolve hyperbranched polyglycidyl ether with a number-average molecular weight (Mn) of 2000-5000 g / mol. Add dibutyltin dilaurate at a concentration of 0.1% to 0.5% of the mass of the hyperbranched polyglycidyl ether. Add 3-isocyanate-propyltriethoxysilane dropwise while stirring. Heat to 58-62℃ and react for 3.5-4.5 hours to allow the isocyanate to evaporate. The cyanate groups react with some of the hydroxyl groups on the surface of hyperbranched polyglycidyl ether to form urethane bonds; then the temperature is lowered to 0-5℃, triethylamine is added as an acid-binding agent, cinnamyl chloride is added dropwise, the temperature is lowered to 0-5℃ and reacted at this temperature for 10-14 hours, so that the acyl chloride groups react with the remaining hydroxyl groups to form ester bonds; after the reaction is completed, the generated triethylamine hydrochloride precipitate is first removed by filtration, the filtrate is added dropwise to diethyl ether to precipitate, and the precipitate is repeatedly washed with diethyl ether and dried under vacuum to obtain the modified hyperbranched polymer precursor; Step (2): Disperse the modified hyperbranched polymer precursor obtained in step (1) in an ethanol / water mixed solvent with a volume ratio of ethanol to water of 6.5:3.5 to 7.5:2.5, and add tannic acid in an amount equal to the mass of the modified hyperbranched polymer precursor. to Stir mechanically at 20-30℃ for 0.5-1.5 hours; then slowly add a 0.05-0.15 mol / L ferric chloride hexahydrate aqueous solution, with the total amount added based on the molar ratio of ferric ions to tannic acid. to The pH was controlled and adjusted to 4.5-5.0 with acetic acid to induce in-situ coordination of iron ions with tannic acid, and the molecular weight cutoff was [value missing]. After dialysis using a dialysis bag to remove unreacted ions, an aqueous stock solution containing an interfacial dissociation agent is obtained. Step (3): Dilute the aqueous stock solution of the interfacial dissociation agent obtained in step (2) to a mass concentration of 20-50 g / L, and add... of Fatty alcohol polyoxyethylene ether The pH of the finishing solution was adjusted to 5.0-6.0 with acetic acid. Step (4): Immerse the desized and scouring polyester / cotton blended fabric in the finishing solution prepared in step (3) and perform a two-dip and two-nip treatment, controlling the nip rate to 75%-85%; place the treated fabric in a 95-105℃ pre-drying condition for 2-4 minutes, and then bake it in a 155-165℃ condition for 1.5-2.5 minutes to induce the hydrolysis and condensation of siloxane groups and self-condensation polymerization, thus completing the interface anchoring; Step (5): The baked fabric is irradiated with ultraviolet light with a wavelength greater than 280nm through an ultraviolet curing device. The irradiation dose is controlled to be 2-4J / cm², which induces the [2+2] photodimerization reaction of the cinnamic acid ester groups on the surface to form a cross-linked hydrophobic shell on the surface of the microcapsule, thus obtaining an eco-friendly green fabric.
[0007] Preferably, the 3-isocyanate-propyltriethoxysilane added in step (1) is added slowly at a rate of 1-2 drops / second under a nitrogen atmosphere.
[0008] Preferably, the dialysis process in step (2) uses a dialysis bag with a molecular weight cutoff of 3500-4000 Da, and dialysis is performed in deionized water for 24-48 hours, during which the deionized water is replaced every 6-8 hours.
[0009] Preferably, in step (4), the polyester / cotton blended fabric has a fiber blending ratio of 65:35 or 50:50 between polyester and cotton.
[0010] Preferably, the ultraviolet curing equipment in step (5) uses an LED light source with a center wavelength of 365nm.
[0011] This invention provides an improved eco-friendly fabric degradation process, which, compared with existing technologies, has the following improvements and advantages: 1. This solution effectively solves the problem of easy loss of degradable components in traditional processes by constructing a specific shell structure. In actual tests, this solution can effectively prevent the loss of functional components during washing and ensure the stability of the fabric during its service life. 2. This solution significantly improves the degradation efficiency after disposal. This solution can precisely trigger the degradation reaction, realizing the catalytic chain scission of polyester components and the accelerated biodegradation of cotton components; 3. This solution enhances the bonding force between functional components and fibers through interface anchoring design. Through the hydrolysis and self-condensation of siloxane groups, it ensures the stable attachment of functional components throughout their entire life cycle. Even in large-scale industrial production scenarios, it can achieve efficient production balance while ensuring whiteness and strength. Detailed Implementation
[0012] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. Example 1:
[0013] This invention provides an eco-friendly fabric degradation process, which is carried out strictly according to the following steps: Before formal preparation, this invention pre-established a dynamic correlation model between the molecular weight Mn of the hyperbranched polymer and the tannic acid loading efficiency and solution dispersion stability. Experimental data showed that when Mn was below 2000 g / mol, the polymer cavity volume was insufficient; when Mn was above 5000 g / mol, intermolecular entanglement intensified. Based on this, in this embodiment, step (1) specifically selected hyperbranched polyglycidyl ether with a number-average molecular weight Mn of 2000 g / mol. Specifically, the hyperbranched polyglycidyl ether was prepared by anionic ring-opening polymerization: using trimethylolpropane as the core initiator, glycidyl monomer was slowly added dropwise at 110°C under potassium hydroxide catalysis, with the monomer to initiator molar ratio being approximately appropriate, and the reaction was controlled until the degree of branching was approximately 0.5. After purification by methanol precipitation, the polymer was obtained, ensuring that it had abundant terminal hydroxyl groups and a suitable internal cavity structure.
[0014] Step (1): In a 500 mL reactor equipped with a mechanical stirrer, condenser, and nitrogen protection device, add anhydrous N,N-dimethylformamide to dissolve hyperbranched polyglycidyl ether with a number-average molecular weight (Mn) of 2000 g / mol, and add dibutyltin dilaurate at 0.1% of the mass of the hyperbranched polyglycidyl ether. Under nitrogen protection, slowly add 3-isocyanopropyltriethoxysilane at a rate of 1 drop / second, and heat to 58 °C for 3.5 hours. This combination of drop rate and temperature helps the isocyanate groups to react smoothly with the primary hydroxyl groups on the terminal units of the hyperbranched polyglycidyl ether molecule to form urethane bonds, avoiding localized gelation caused by vigorous reaction.
[0015] The temperature was then lowered to 0°C, and triethylamine was added as an acid-binding agent. Cinnamyl chloride was then added dropwise, and the temperature was lowered to 0°C and reacted at this temperature for 10 hours. This allowed the acyl chloride groups to react with the remaining unreacted primary hydroxyl groups in the molecular chain and the secondary hydroxyl groups on the internal linear units to form ester bonds. After the reaction was completed, the resulting triethylamine hydrochloride precipitate was first removed by filtration. The filtrate was then added dropwise to diethyl ether to precipitate the precipitate, and the mixture was repeatedly washed with diethyl ether. After vacuum drying, the modified hyperbranched polymer precursor was obtained.
[0016] Step (2): The modified hyperbranched polymer precursor obtained in step (1) was dispersed in an ethanol / water mixed solvent with a volume ratio of 6.5:3.5. Tannic acid was added, with the amount being 30% of the mass of the modified hyperbranched polymer precursor. The mixture was mechanically stirred at 20°C for 0.5 hours. Subsequently, a 0.05 mol / L ferric chloride hexahydrate aqueous solution was slowly added dropwise, with the total amount added controlled according to a ferric ion to tannic acid molar ratio of 1:4. The pH was adjusted to 4.5 with acetic acid to induce in-situ coordination between ferric ions and tannic acid. The solution was dialyzed in deionized water for 24 hours using a dialysis bag with a molecular weight cutoff of 3500 Da (the deionized water was replaced every 6 hours during this period) to remove unreacted ions, resulting in an aqueous stock solution dispersed with an interfacial dissociation agent. This step constructs a catalytically active metal-polyphenol network core through in-situ coordination. Meanwhile, the specific microcapsule structure formed by the hyperbranched polymer in the aqueous phase encapsulates the hydrophobic siloxane segments inside or at the interface, effectively inhibiting the macroscopic crosslinking and gelation of silanol groups during long-term dialysis.
[0017] Step (3): Dilute the aqueous solution of the interfacial dissociation agent obtained in step (2) to a mass concentration of 20 g / L, add 1 g / L of C12-14 fatty alcohol polyoxyethylene ether (AEO-9), and adjust the pH of the finishing solution to 5.0 with acetic acid.
[0018] Step (4): Select a polyester / cotton blended fabric with a ratio of 65:35. Immerse the desized and scouring polyester / cotton blended fabric in the finishing solution prepared in step (3) for a two-dip and two-nip treatment, controlling the nip rate to 75%. Pre-dry the treated fabric at 95°C for 2 minutes, and then bake it at 155°C for 1.5 minutes. This high-temperature baking process induces the hydrolysis and condensation of siloxane groups and self-condensation polymerization, completing interfacial anchoring on the fiber surface.
[0019] Step (5): The baked fabric is irradiated with ultraviolet light (UV) with a wavelength greater than 280nm using a UV curing device with a center wavelength of 365nm LED light source, and the irradiation dose is controlled at 2J / cm². This dose of UV light is sufficient to induce a [2+2] photodimerization reaction of the surface cinnamate groups, forming a cross-linked hydrophobic shell on the surface of the microcapsules, thus producing an eco-friendly fabric. During use, the fabric prepared by this process effectively prevents the loss of iron ions and yellowing due to the protection of the hydrophobic shell; after disposal, the shell breaks down and releases a catalyst, promoting the degradation of the fabric. Example 2:
[0020] This embodiment provides an eco-friendly fabric degradation process, designed to verify the overall performance balance under standard process conditions.
[0021] Step (1): In a reactor equipped with a mechanical stirrer, a condenser, and a nitrogen protection device, anhydrous N,N-dimethylformamide was dissolved in hyperbranched polyglycidyl ether with a number-average molecular weight (Mn) of 3500 g / mol. This molecular weight helps to balance the penetration and loading capacity of the finishing agent into the amorphous region of the fiber. Dibutyltin dilaurate was added at 0.3% of the mass of the hyperbranched polyglycidyl ether. 3-isocyanate-propyltriethoxysilane was added dropwise under stirring, and the temperature was raised to 60°C for 4.0 hours. During this process, the reaction temperature and the amount of catalyst were matched to ensure suitable reaction activity. Subsequently, the temperature was lowered to 3°C, triethylamine was added as an acid-binding agent, and cinnamoyl chloride was added dropwise. The reaction was carried out at this temperature for 12 hours. After the reaction, the treatment was the same as in Example 1 to obtain the modified hyperbranched polymer precursor.
[0022] Step (2): The modified hyperbranched polymer precursor obtained in step (1) was dispersed in a mixed solvent of ethanol and water at a volume ratio of 7:3. Tannic acid was added at 45% of the precursor mass, and the mixture was mechanically stirred at 25°C (room temperature) for 1.0 hour. Subsequently, 0.10 mol / L ferric chloride hexahydrate aqueous solution was added dropwise, with the amount added corresponding to a molar ratio of ferric ions to tannic acid of 1:3.2. The pH was adjusted to 4.8 with acetic acid. A dialysis bag with a molecular weight cutoff of 3800 Da was used for dialysis, and the dialysis time was controlled at 36 hours.
[0023] Step (3): Dilute the aqueous solution of the interface dissociation agent to a mass concentration of 35 g / L, add 1.5 g / L of AEO-9, and adjust the pH of the finishing solution to 5.5 with acetic acid.
[0024] Step (4): Immerse the desized and scouring polyester / cotton blended fabric (blending ratio 50:50) in the finishing solution prepared in step (3) for two dips and two nips, controlling the nips rate to 80%. Place the treated fabric at 100℃ for 3 minutes to pre-dry, and then bake at 160℃ for 2 minutes.
[0025] Step (5): The baked fabric is irradiated with ultraviolet light with a wavelength greater than 280nm using an ultraviolet curing device, and the irradiation dose is controlled at 3J / cm². In this embodiment, by using a moderate baking temperature and ultraviolet irradiation dose, the basic degree of crosslinking is ensured while maintaining the hand feel and whiteness of the fabric, and the density of the hydrophobic shell meets the requirements for excellent washability. Example 3:
[0026] This embodiment provides an eco-friendly fabric degradation process that aims to improve the durability of fabrics by increasing cross-linking density.
[0027] Step (1): In a reactor equipped with a mechanical stirrer, condenser, and nitrogen protection device, anhydrous N,N-dimethylformamide was added to dissolve hyperbranched polyglycidyl ether with a number-average molecular weight (Mn) of 5000 g / mol. The high molecular weight provides more terminal hydroxyl sites for grafting. This polymer was synthesized via a one-step proton transfer polymerization method: using glycerol as an initiator, glycidyl monomers were polymerized at 120°C in the presence of an alkaline catalyst. The reaction product was repeatedly precipitated and washed with acetone to obtain a specific raw material with a polydispersity index less than 1.5, ensuring the regularity of its branched structure. Before the reaction began, the hyperbranched polyglycidyl ether was fully dissolved. The addition of 3-isocyanate-propyltriethoxysilane was controlled at 2 drops / second, and the amount of dibutyltin dilaurate added was set to 0.5% of the mass of the hyperbranched polymer to promote the reaction under high viscosity conditions. The reaction temperature was set at 62°C, and the reaction time was 4.5 hours. Subsequently, the temperature was lowered to 5°C, cinnamoyl chloride was added dropwise, and the reaction time was 14 hours.
[0028] Step (2): Disperse the precursor in an ethanol / water mixture with a volume ratio of 7.5:2.5, add tannic acid at 60% of the precursor mass, and mechanically stir at 30°C for 1.5 hours. Then, add dropwise a 0.15 mol / L ferric chloride hexahydrate aqueous solution at a molar ratio of ferric ions to tannic acid of 1:2.5, and adjust the pH to 5.0. Dialysis was performed for 48 hours using a dialysis bag with a molecular weight cutoff of 4000 Da.
[0029] Step (3): Dilute the aqueous stock solution of the interface dissociation agent to a mass concentration of 50 g / L, add 2 g / L of AEO-9, and adjust the pH to 6.0.
[0030] Step (4): Select a fabric with a polyester / cotton blend ratio of 65:35, control the roll-off rate at 85%, pre-dry at 105℃ for 4 minutes, and bake at 165℃ for 2.5 minutes.
[0031] Step (5): The UV curing irradiation dose is increased to 4 J / cm². Under this process condition, the high concentration of finishing agent, combined with long-term high-temperature baking and high-dose UV irradiation, constructs a dense and strong cross-linked network on the fabric surface, which significantly improves the fabric's washability and abrasion resistance, allowing the internal catalytic components to be well preserved during long-term use, and only releasing their activity after being triggered by the waste environment. Example 4:
[0032] This embodiment provides an eco-friendly fabric degradation process that focuses on optimizing the stability of the reaction intermediate state and uses medium to low process parameters.
[0033] Step (1): Hyperbranched polyglycidyl ether with Mn of 2750 g / mol was selected, and 0.2% dibutyltin dilaurate was added. The mixture was heated to 59°C and reacted for 3.8 hours. Then the temperature was lowered to 2°C, triethylamine was added as an acid-binding agent, cinnamoyl chloride was added dropwise, the temperature was lowered to 2°C, and the mixture was reacted at this temperature for 11 hours.
[0034] Step (2): The precursor was dispersed in an ethanol / water mixture with a volume ratio of 6.8:3.2. Tannic acid was added at 38% of the precursor mass, and the mixture was mechanically stirred at 22°C for 0.8 hours. Subsequently, a 0.08 mol / L ferric chloride hexahydrate aqueous solution was slowly added dropwise, with the total amount added controlled according to a ferric ion to tannic acid molar ratio of 1:3.6. The pH was adjusted to 4.6 with acetic acid. Dialysis was performed using a dialysis bag with a molecular weight cutoff of 3600 Da.
[0035] Step (3): Dilute the aqueous solution of the interface dissociation agent to a mass concentration of 28 g / L, add 1.2 g / L of AEO-9, and adjust the pH of the finishing solution to 5.2 with acetic acid.
[0036] Step (4): Immerse the desized and scouring polyester / cotton blended fabric in the finishing solution and perform a two-dip and two-nip treatment, controlling the nip rate to 78%. Place the treated fabric at 98℃ for 2.5 minutes for pre-drying, and then bake at 158℃ for 1.8 minutes.
[0037] Step (5): Control the ultraviolet irradiation dose to 2.5 J / cm². In this embodiment, the dispersion stability of the modified hyperbranched polymer in the aqueous medium was optimized by finely controlling the pH value and solvent ratio, reducing the risk of aggregation of the finishing solution during storage, thereby ensuring that the microcapsules applied to the fabric are evenly distributed, so that the degradation performance of the final fabric exhibits good consistency in different areas. Example 5:
[0038] This embodiment provides an eco-friendly fabric degradation process that focuses on balancing industrial production efficiency and uses medium to high process parameters.
[0039] Step (1): Hyperbranched polyglycidyl ether with Mn of 4250 g / mol was selected, and 0.4% dibutyltin dilaurate was added. The mixture was heated to 61°C and reacted for 4.2 hours. Then the temperature was lowered to 4°C, triethylamine was added as an acid-binding agent, cinnamoyl chloride was added dropwise, the temperature was lowered to 4°C, and the mixture was reacted at this temperature for 13 hours.
[0040] Step (2): The precursor was dispersed in an ethanol / water mixture with a volume ratio of 7.2:2.8. Tannic acid was added at 52% of the precursor mass, and the mixture was mechanically stirred at 28°C for 1.2 hours. Subsequently, a 0.12 mol / L aqueous solution of ferric chloride hexahydrate was slowly added dropwise, with the total amount added controlled according to a ferric ion to tannic acid molar ratio of 1:2.8. The pH was adjusted to 4.9 with acetic acid. Dialysis was performed using a dialysis bag with a molecular weight cutoff of 3900 Da.
[0041] Step (3): Dilute the aqueous solution of the interface dissociation agent to a mass concentration of 42 g / L, add 1.8 g / L of AEO-9, and adjust the pH of the finishing solution to 5.8 with acetic acid.
[0042] Step (4): Pre-bake the treated fabric at 102°C for 3.5 minutes, and then bake it at 162°C for 2.2 minutes.
[0043] Step (5): Control the ultraviolet irradiation dose to 3.5 J / cm². This embodiment demonstrates that even when the process parameters are at a medium to high level, a structurally intact interface dissociator can still be obtained. Through appropriate baking and light irradiation, an effective balance between production efficiency and product performance (such as whiteness and strength retention) is achieved, making it suitable for cost-sensitive large-scale production scenarios.
[0044] Comparative Example 1: This comparative example provides a fabric treatment process, which differs from Example 1 only in that the UV curing process in step (5) is omitted. That is, the fabric is directly used as a finished product after padding and baking. Due to the lack of UV-induced [2+2] photodimerization reaction of cinnamate groups, the microcapsule surface failed to form a cross-linked hydrophobic shell, which resulted in the internal iron-tannic acid complex being exposed and easily lost in subsequent washing tests. Furthermore, the iron ions were directly exposed to air and light, causing the fabric to show obvious yellowing during storage, and the strength retention rate during the wearing period was reduced due to premature catalyst release.
[0045] Comparative Example 2: This comparative example provides a fabric treatment process that differs from Example 1 only in that tannic acid and ferric chloride hexahydrate are not added in step (2), and only hollow modified hyperbranched polymer microcapsules are prepared; the remaining steps are consistent with Example 1. Although the fabric prepared in this comparative example has the interfacial anchoring effect and photocrosslinking shell brought by siloxane, due to the lack of a core degradation engine (i.e., iron-tannic acid complex), its degradation behavior in soil burial tests after disposal is no different from that of ordinary polyester / cotton blended fabrics. It cannot achieve catalytic chain scission of polyester components and accelerated corrosion of cotton components, which confirms the necessity of metal-polyphenol coordination centers in the degradation process.
[0046] Comparative Example 3: This comparative example provides a fabric treatment process that differs from Example 1 in that 3-isocyanate-propyltriethoxysilane is not added in step (1), meaning the modified polymer does not possess siloxane anchoring groups. The remaining steps are consistent with Example 1. Due to the lack of siloxane groups that can covalently bond with the hydroxyl groups of cotton fibers and self-condense on the polyester surface, the finishing agent only adheres to the fabric surface through physical adsorption. After a standard water washing test, most of the finishing agent falls off, resulting in a significant decrease in the fabric's degradation performance during disposal, failing to achieve the expected ecological degradation effect. This confirms the crucial role of interface anchoring design in functional durability.
[0047] Verification experiment: To more intuitively demonstrate the differences in technical effects between the above embodiments and the comparative examples, the following performance tests were conducted.
[0048] Testing standards: Washing strength retention rate: After 20 washes according to AATCC 61-2A standard, the retention rate of the fabric's breaking strength relative to the original condition is tested.
[0049] Soil burial degradation weight loss rate: The weight loss rate after burial in standard soil for 90 days, according to ISO 11721 standard.
[0050] Whiteness Index: The initial whiteness (W) of the finished fabric is determined using the CIE whiteness formula.
[0051] Specific testing process: All tests were conducted under constant temperature and humidity conditions. Each sample was tested five times, and the average value was taken as the final result. For the soil burial test, standard humus soil was used, with humidity controlled at 60% and temperature maintained at 25±2℃. Samples were taken out every 30 days for cleaning, drying, and weighing.
[0052] Data table: Table 1: Summary of performance test data for each embodiment and comparative example
[0053] Analysis of the data in Table 1 shows that the eco-friendly fabric degradation process of this invention successfully achieves a dual improvement in fabric durability and degradability through a core-shell-claw synergistic design. Comparative examples 1-5 show that with increasing finishing solution concentration and UV irradiation dose, the fabric's wash strength retention rate and soil burial degradation weight loss rate exhibit an upward trend. The comparative test results further confirm the necessity of each key step.
[0054] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
Claims
1. An eco-friendly fabric degradation process, characterized in that, Includes the following steps: Step (1): In a reactor equipped with a mechanical stirrer, a condenser, and a nitrogen protection device, add anhydrous N,N-dimethylformamide to dissolve hyperbranched polyglycidyl ether with a number-average molecular weight (Mn) of 2000-5000 g / mol. Add dibutyltin dilaurate at a concentration of 0.1% to 0.5% of the mass of the hyperbranched polyglycidyl ether. Add 3-isocyanate-propyltriethoxysilane dropwise while stirring. Heat to 58-62℃ and react for 3.5-4.5 hours to allow the isocyanate to evaporate. The cyanate groups react with some of the hydroxyl groups on the surface of hyperbranched polyglycidyl ether to form urethane bonds; then the temperature is lowered to 0-5℃, triethylamine is added as an acid-binding agent, cinnamyl chloride is added dropwise, the temperature is lowered to 0-5℃ and reacted at this temperature for 10-14 hours, so that the acyl chloride groups react with the remaining hydroxyl groups to form ester bonds; after the reaction is completed, the generated triethylamine hydrochloride precipitate is first removed by filtration, the filtrate is added dropwise to diethyl ether to precipitate, and the precipitate is repeatedly washed with diethyl ether and dried under vacuum to obtain the modified hyperbranched polymer precursor; Step (2): Disperse the modified hyperbranched polymer precursor obtained in step (1) in an ethanol / water mixed solvent with a volume ratio of ethanol to water of 6.5:3.5 to 7.5:2.5, and add tannic acid in an amount equal to the mass of the modified hyperbranched polymer precursor. to Stir mechanically at 20-30℃ for 0.5-1.5 hours; then slowly add a 0.05-0.15 mol / L ferric chloride hexahydrate aqueous solution, with the total amount added based on the molar ratio of ferric ions to tannic acid. to The pH was controlled and adjusted to 4.5-5.0 with acetic acid to induce in-situ coordination of iron ions with tannic acid, and the molecular weight cutoff was [value missing]. After dialysis using a dialysis bag to remove unreacted ions, an aqueous stock solution containing an interfacial dissociation agent is obtained. Step (3): Dilute the aqueous stock solution of the interfacial dissociation agent obtained in step (2) to a mass concentration of 20-50 g / L, and add... of Fatty alcohol polyoxyethylene ether The pH of the finishing solution was adjusted to 5.0-6.0 with acetic acid. Step (4): Immerse the desized and scouring polyester / cotton blended fabric in the finishing solution prepared in step (3) and perform a two-dip and two-nip treatment, controlling the nip rate to 75%-85%; place the treated fabric in a 95-105℃ pre-drying condition for 2-4 minutes, and then bake it in a 155-165℃ condition for 1.5-2.5 minutes to induce the hydrolysis and condensation of siloxane groups and self-condensation polymerization, thus completing the interface anchoring; Step (5): The baked fabric is irradiated with ultraviolet light with a wavelength greater than 280nm through an ultraviolet curing device. The irradiation dose is controlled to be 2-4J / cm², which induces the [2+2] photodimerization reaction of the cinnamic acid ester groups on the surface to form a cross-linked hydrophobic shell on the surface of the microcapsule, thus obtaining an eco-friendly green fabric.
2. The eco-friendly fabric degradation process according to claim 1, characterized in that, The 3-isocyanate-propyltriethoxysilane described in step (1) is added slowly at a rate of 1-2 drops / second under a nitrogen atmosphere.
3. The eco-friendly fabric degradation process according to claim 1, characterized in that, The dialysis process described in step (2) uses a dialysis bag with a molecular weight cutoff of 3500-4000 Da and dialysis in deionized water for 24-48 hours, during which the deionized water is replaced every 6-8 hours.
4. The eco-friendly fabric degradation process according to claim 1, characterized in that, In step (4), the polyester / cotton blended fabric has a fiber blending ratio of 65:35 or 50:50 between polyester and cotton.
5. The eco-friendly fabric degradation process according to claim 1, characterized in that, The ultraviolet curing equipment described in step (5) uses an LED light source with a center wavelength of 365nm.