Preparation of recycled cellulose-polyvinyl alcohol reinforced co-blended fibers based on waste cotton

Preparation of recycled cellulose-polyvinyl alcohol reinforced co-blended fibers based on waste cotton | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Preparation of recycled cellulose-polyvinyl alcohol reinforced co-blended fibers based on waste cotton Linlin Wang, Hui Zhao, Lili Meng, Menglei Liu, Lixia Jia This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5173409/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 23 Jan, 2026 Read the published version in Cellulose → Version 1 posted 10 You are reading this latest preprint version Abstract In order to achieve sustainable development of resources and reduce environmental pollution, it is particularly important to accelerate the use of renewable resources. Cellulose is an abundant renewable resource with biocompatible, degradable and recyclable characteristics. In order to further improve the utilization of cellulose, 1-butyl-3-methylimidazolium chloride ([Bmim]Cl)/dimethylsulfoxide (DMSO) was used to dissolve and recover cellulose from waste cotton, and regenerated cellulose (RCF) and regenerated cellulose-poly(vinyl alcohol) blended fibres (RCF/PVA) were prepared by wet spinning technology, and the pigments extracted from Pu-erh Tea were used for dyeing performance investigation of RCF/PVA. The dyeing performance of RCF/PVA was investigated. The experiments showed that, compared with RCF, the strength of RCF/PVA with 15 % PVA was improved, and the residual carbon at 700 ℃ of thermal decomposition was reduced from 21.4 % to 0.1 %. With the increase of polyvinyl alcohol content, RCF/PVA has better dyeing effect than pure cellulose regenerated fibre on the natural pigment extracted from Pu-erh tea, and the preparation of RCF/PVA provides a new way of researching new composite fibre materials. Waste cotton Polyvinyl alcohol Composite fiber Wet spinning Regenerated cellulose Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 1. INTRODUCTION At present, the global development of energy and its related industries has gradually formed a trend of low carbon. According to the requirements of carbon peak and carbon neutrality goals, a green low-carbon circular development economic system will be initially formed in 2025, and the proportion of non-fossil energy consumption will reach about 20%. As a green, renewable and recyclable resource, cellulose is of great significance to achieve carbon peak and carbon neutrality by rationally using cellulose instead of non-renewable resources(Acharya et al., 2021 ; Dorugade et al., 2023 ; Garces, Ngo, Ayranci & Boluk, 2024 ; Jarvis, 2017 ; Sarker et al., 2018 ; Shaghaleh, Xu & Wang, 2018 ; Zainul Armir et al., 2021 ). Cotton fiber is an important textile raw material, the total amount of fiber processing in China is about 50 million tons per year, and the generated waste textiles is about 20 million tons, while the comprehensive utilization rate of waste textiles is only 15%, and the recycling capacity and level of waste textiles still have greater room for improvement. Therefore the recycling of waste cotton textiles not only reduces the pollution of the environment, but also improves the reuse of resources(Chang, Kao, Chen, Zhang & Wu, 2023 ; Nasri-Nasrabadi & Byrne, 2020 ; Rosson & Byrne, 2022 ; Wu et al., 2023 ; Xie, Hong, Zeng, Dai & Wagner, 2021 ). At present, for the recycling of waste cotton textiles are mainly physical and chemical methods. Burial or incineration is not only a waste of resources but also pollutes the environment(Sun et al., 2021 ; C. Wang et al., 2021 ). Mechanical crushing method, not conducive to the extraction of blended or interwoven fibers, which also greatly limits the scope of application(Ruiz-Caldas et al., 2022 ; Trilokesh, Bavadharani, Mahapriyadarshini, Janani & Uppuluri, 2020 ; Yi et al., 2020 ). Chemical method is to use the solvent to dissolve the fiber for regeneration, but there are problems of low dissolution efficiency or solvent recontamination(Q. Cheng et al., 2021 ; X.-W. Cheng, Tang, Yao & Yang, 2019 ; Gu, Jiang, Liu, Prempeh & Smalyukh, 2016 ; Ishida, 2020 ). The main problem with the reuse of cellulose is that cellulose is neither water-soluble nor soluble in general organic solvents, due to the presence of hydrogen bonds between cellulose molecules. The full use of cellulose needs to destroy the hydrogen bonds between and within the cellulose molecules. At present, the methods of chemical preparation of waste cotton fabric into reclaimed cellulose fiber mainly include cuprammonium method(Shen, Sun & Zhou, 2023 ), Sodium hydroxide/urea/thiourea method(El Bouazzaoui, Habsaoui & Touhami, 2022 ), LiCl/DMAc method(Q. Wang et al., 2023 ), N-methylmorph oxide (NMMO) solvent method and ionic liquid method(Haule, Michael Carr & Rigout, 2015; Zhao et al., 2023 ). Although cupramine solution is recyclable, corrosive substances need to be added in the process of preparing reclaimed cellulose fiber from cupramine solution. Will cause pollution to the environment; LiCl/DMAc method has high cost, low efficiency and pollution to the environment. In the N-methylmorpholine oxide (NMMO) solvent method, NMMO is prone to discoloration and decomposition explosion under high temperature conditions. Ionic liquid has become a hot research field in preparing regenerated cellulose due to its high thermal stability, chemical stability and recyclability. Ionic liquids have the advantages of recyclability and non-pollution, which have become the hotspot of recent research in various fields(Huang et al., 2024 ; Salama & Hesemann, 2020 ; Shamsuri, Abdan & Jamil, 2021 ; Sharma et al., 2022 ). Studies have shown that adding specific aprotic solvents to ionic liquids can effectively improve the dissolution effect of cellulose, and aprotic solvents will make cellulose swell, which can effectively promote the ionic liquid into the cellulose interior(El Seoud, Bioni & Dignani, 2021 ; Ma et al., 2020 ; Mqoni, Singh, Bahadur, Hashemi & Ramjugernath, 2022 ; Ren et al., 2021 ; Stolarska, Pawlowska-Zygarowicz, Soto, Rodríguez & Smiglak, 2017 ; Verma et al., 2019 ; Y. Zhou et al., 2022 ). However, the resulting regenerated cellulose suffers from poor mechanical properties(Pereira, Pinto, Santos & Correia, 2024 ). Therefore, Zhuo Cao co-dissolved cellulose and polyacrylonitrile in ionic liquid, and wet-spun to improve the mechanical properties of the regenerated cellulose fiber, but the polyacrylonitrile had the defect of alkali resistance(Azimi et al., 2022 ; Cao, Li, Suo, Liu & Lu, 2020 ). Yuhui Ci spun a composite fiber with good mechanical properties by dissolving cellulose and thermoplastic polyurethane (TPU) at the same time to provide a feasible method for the study of composite materials(Ci, Lv, Yang, Du & Tang, 2024 ). Among many polymers, polyvinyl alcohol (PVA) is a biodegradable green polymer compound with good fiber-forming properties, tensile strength, good resistance to chemicals and corrosion, and polyvinyl alcohol rich in hydroxyl structure can be very good compatibility with cellulose, and textile fibers in the vinylon is a synthetic fiber spun from PVA as raw material(Z. Zhou et al., 2022 ). Therefore, the recycled cellulose-polyvinyl alcohol blended fibers were prepared by wet spinning technology using low-cost waste indigo denim cotton yarn as raw material, and dissolving waste cotton and polyvinyl alcohol into spinning solution using [Bmim]Cl/DMSO. In addition, the regenerated cellulose fibers and regenerated cellulose/poly(vinyl alcohol)-enhanced co-blended fibers were dyed using Pu-erh tea extract to investigate the dyeing performance of the enhanced co-blended fibers with different PVA contents on the natural dyes extracted from Pu-erh tea. 2. EXPERIMENTAL 2.1. Materials 1-butyl-3-methylimidazole chloride ([Bmim]Cl), dimethyl sulfoxide (DMSO) and polyvinyl alcohol (PVA) were purchased from Shanghai Ala Liability Co., LTD. N, N-dimethylformamide and sodium hydroxide were purchased from Tianjin Zhiyuan Chemical Reagent Co., LTD., hydrogen peroxide was purchased from Tianjin Yongsheng Fine Chemical Co., LTD., insurance powder was purchased from Tianjin Damao Chemical Reagent Factory, methanol was purchased from Tianjin Xinbaite Chemical Co., LTD. Deionized water (16.8 MΩ·cm − 1 , Millipore Milli-Q) made in the lab. 2.2. Dissolving the Waste Cotton Waste indigo cotton yarns were sterilized and washed using aqueous hydrogen peroxide (1 wt%) and then dried to be decolorized. Accurately measure 300 mL of N,N-dimethylmethylamine was transferred to a 1000 mL volumetric flask, accurately weigh 9 g of NaOH and 10 g of Na 2 S 2 O 4 were added to the volumetric flask, and the volume was fixed with distilled water, and then shaken well as the stripping solution for use. In the sufficient amount of NaOH and Na 2 S 2 O 4 , the indigo dyed on the fibers were all reduced to yellow soluble cryptochrome salts, and under the adsorption and solubilizing effect of the stripping solution, the cryptochrome salts dissolved into DMF. Under the adsorption and solubilization effect of the color stripping solution, the cryptochrome salt was dissolved into DMF solution. Accurately weigh 0.2 g of baked dyed cotton yarn in a beaker, add 50 mL of color stripping solution to it, put it in a 70 ℃ water bath at a constant temperature to strip the color for 15 min, then wash, dry, and cut into pieces. Put 0.2 g of stripped cotton into the DMSO/B(mim)Cl mixed solution (molar ratio of 1:1), heat up to 120 ℃ and add 5%, 10%, 15% of the cotton mass of PVA, mechanical stirring for 4 h, followed by the obtained homogeneous spinning solution. 2.3. Preparation of regenerated cellulose and polyvinyl alcohol blend fiber The spinning liquid was placed in a syringe and peristaltic pumped at 8 ml/h, extruded through a 1 mm diameter exit hole, stretched and then solidified in a methanol coagulation bath at 20 ℃. After the methanol bath through the winding device collection (take cellulose samples with silver nitrate solution to detect the presence of ionic liquids, if there is no white precipitate produced, it is proved that the ionic liquids in the hybrid fibers are removed), natural drying to obtain regenerated cellulose - polyvinyl alcohol co-blended fibers, the preparation process shown in Fig. 1 . The blended fibers with PVA mass ratio of 0%, 5%, 10% and 15% were named RCF, RCF/PVA-5, RCF/PVA-10 and RCF/PVA-15, respectively. 2.4. Dyeing of the Extracted Process Pu-erh tea extract pigment: weigh 25 g of Pu-erh tea, immersed in a round-bottomed flask containing 150 ml of deionized water, placed in a water bath and heated to 95 ℃, kept warm for 60 min, filtered the tea residue, the extract was used as a dye solution for use. Dyeing process: take 100 ml of dye solution in a beaker, add 0.1 g citric acid, heating to 40 ℃, respectively, will be different types of 2 g co-blended fibers added to the dye solution after heating, heating rate of 2 ℃ / min, when the temperature reaches 90 ℃, insulation 50 min, and then cool down the temperature of the water washing and drying, will be dyed cellulose to be measured. After dyeing the composite fiber in 2g / L soap flake solution to 49 ℃, stirring 1h after drying to be measured. 2.5. Characterization Morphology measurements High resolution field emission scanning electron microscopy (JSM-7610F Plus Japan) was used to observe the fiber display and cross section. The fiber cross section sample was obtained by the Haber slicer, the fiber sample was fixed on the sample table with conductive adhesive, and then the sample was sprayed with gold for 120 s, and analyzed under the accelerated voltage of 5.0 KV. The SEM images of fiber surface and cross section with different multiples were obtained. Chemical structure characterization In order to observe whether the mixed fiber contains PVA, Fourier transform infrared spectrometer (FTIR Vertical-70-RAMI Japan) was used to test the fiber. The fiber was dried in a constant temperature oven at 80 ℃ for 12 h, and then crushed to obtain the sample. The sample was prepared by KBr tablet. The scanning accuracy is 4 cm − 1 and the scanning range is 400 to 4000 cm − 1 . Crystallinity analysis In order to observe the crystal change of the mixed fiber, X-ray powder diffractometer (Bruker D8 Advance Germany) was used to test the fiber, using CuKa target, X-ray wavelength of 1.5405A, scanning Angle range of 5–60 °, speed of 8 °/min, operating voltage of 40 kV, current of 25 mA.The XRD patterns had been smoothed by MDI Jade and carried out with Origin software. Thermal stability analysis The thermal stability of the fibers was tested using a thermogravimetric-differential thermal thermal analyzer (TG-DTG HITACHI STA7300, Japan) with a temperature increase rate of 15 ℃/min and an airflow rate of 200 ml/min to 700°C. The TG-DTG plots of the aerogels were obtained. Mechanical properties measurements The breaking strength and tensile strength of fibers can be obtained by testing the mechanical properties of fibers with a strength meter ( 008E China). The test temperature was 30 ℃, the humidity was 30%, the fiber holding length was 50 mm, and the stretching rate was 10 mm/min. Each cellulose sample was repeated for 12 times, and the results were averaged. Color measurements The K/S values, Obtained by spectrophotometer(Ultra Scan PRO, Hunter Lab, USA) CIE L* a* b* C* and h o coordinates were obtained using a Datacolor 850 spectrophotometer, which includes UV and specular components and utilizes illuminant D65 and 10 o standard observer) . 3. RESULTS AND DISCUSSION 3.1. Morphological characteristics of regenerated cellulose-polyvinyl alcohol blended fibers In order to observe the apparent phenomena of the fibers after spinning, the cellulose was observed by scanning electron microscopy.The morphological characteristics of RCF and RCF/PVA composite fibers are shown in Fig. 2 , from which it can be seen that the diameter of the fibers is about 100–120 µm, and that the diameter of RCF is larger than that of RCF/PVA, and the diameter of RCF/PVA decreases gradually with the increase of PVA content. From Fig. 2 (a-c), it can be seen that the surface of RCF is relatively smooth, without cracks and grooves, and no hollow phenomenon was found from the cross-section, which indicates that solvent substitution of RCF in the solidification bath did not have too much effect on the surface morphology of the fibers. From Fig. 2 (d-l), it can be seen that with the increase of PVA content, the surface of the fibers with cracks and grooves on the surface gradually showed relatively smooth, which may be caused by the different rates of solvent substitution between cellulose and PVA in the solidification bath of RCF/PVA. The cross-section showed cracks in the fibers but not hollow, which may be due to the deformation of the fibers under external forces when using a haft slicer, resulting in deformation of the cross-section. The co-blended fibers were observed by SEM to be fibre-forming and could satisfy the spinnability. 3.2. Chemical structure of regenerated cellulose-polyvinyl alcohol blend fiber The chemical structure information of RCF and RCF/PVA was obtained using FT-IR spectroscopy, and the IR spectral information is shown in Fig. 3 . The absorption peak of RCF near 3400 cm − 1 is the telescopic vibrational peak of -OH, and the characteristic peaks of -CH in cellulose are at around 2900 cm − 1 , the bending vibrational peak of -CH at around 1426 cm − 1 , and the C-O at around 1156 cm − 1 . -C asymmetric stretching vibration peak. The formed RCF/PVA retains the characteristic peak of cellulose, the absorption peak of -OH is shifted to 3355 cm − 1 due to hydrogen bonding, the absorption peak around 3200 cm − 1 retains the -OH absorption peak of PVA, and the characteristic peak around 2900 cm − 1 is the -CH-symmetric telescoping vibration peak of cellulose and PVA. From the FT-IR spectra, it can be obtained that the chemical structure of cellulose did not change after the ionic liquid treatment, and the mixed fibers contained PVA, which was not lost in the solidification bath. In order to further verify the crystalline structure of the prepared RCF/PVA, XRD analysis of RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 was carried out using X-ray diffractometer. As can be seen in Fig. 4 , the diffraction peak of RCF at 2θ of 20.8 corresponds to the cellulose type II crystal type, indicating that the cellulose in the waste cotton was transformed from cellulose type I to cellulose type II in the ionic liquid co-solvent solubilization. The prepared RCF/PVA showed a new diffraction peak at 22.4, which is a unique diffraction peak of PVA. From the figure, we can see that the diffraction peak at 22.4 is not very obvious, on the one hand, it is because cellulose and PVA precipitated in the solidification bath in the process of cellulose and PVA chain entanglement phenomenon, and on the other hand, it is because of the addition of a smaller amount of PVA, in the X-ray did not appear obvious diffraction peaks. The diffraction peaks appeared obviously under X-ray. In terms of crystallinity, the crystallinity of RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 were 46%, 51.6%, 61.9%, and 67.9%, respectively, and the crystallinity of the mixed cellulose increased with the increase of PVA content. 3.3. Thermal stability of regenerated cellulose-polyvinyl alcohol blend fiber The thermal stability of RCF and RCF/PVA in air was investigated by thermogravimetric method, and the TG and DTG curves of RCF and RCF/PVA are shown in Fig. 5 . As can be seen from the figure, with the rise in temperature RCF weight loss is mainly divided into two stages, the first stage is below 150 ℃, in the stage RCF is mainly water volatilization; the second stage is between 150–600 ℃, in the stage of the maximum rate of thermal decomposition temperature of 328 ℃, the stage of the decomposition of cellulose to produce CO 2 and water, with the evaporation of CO 2 and water the weight of the larger changes in the weight, mainly for cellulose thermal cracking. The weight of RCF was basically stable after 600 ℃, and the residual carbon at 700 ℃ was 21.4%. Preparation of RCF/PVA in the heat process there are mainly three stages of weight loss, the first stage is below 150 ℃, in the stage is mainly in line with the volatilization of water in the fiber, the second stage is 150–400 ℃, in the stage of thermal decomposition is mainly cellulose decomposition of CO 2 and water, while the PVA generates water, acetic acid, acetaldehyde, etc.; the third stage is 400–600 ℃, in the stage of composite fibers is mainly decomposed into acetaldehyde. The third stage is 400–600 ℃, in this stage is mainly the composite fiber PVA decomposition into acetic acid, acetaldehyde, etc. continue to decompose into CO 2 and water. 600 ℃ after the weight of RCF is basically stable, and the residual carbon of RCF/PVA-5 at 700 ℃ is 0.1%, which is mainly due to the purity of PVA is very high, will be decomposed into CO 2 and water completely after reaching a certain temperature. While the residual carbon-carbon bond aromatization of cellulose after a certain temperature eventually forms charcoal, levogluconic anhydride condensation to form levoglucose further forms a liquid mixture of wood tar, and impurities in the cellulose also remain in the residual carbon(Fan et al., 2022 ). 3.4. Mechanical properties of regenerated cellulose-polyvinyl alcohol blend fibers Regenerated cellulose fibers have good breaking strength but low elongation due to high crystallinity and regular molecular arrangement in the fibers. Therefore, the effects of different polyvinyl alcohol additions on the mechanical properties of regenerated cellulose fibers were explored, and the tensile strength and elongation at break of RCF and RCF/PVA are shown in Fig. 6 (a). The tensile strength of the blended fibers increased with the increase of PVA content, mainly because PVA formed more hydrogen bonds with cellulose, while the PVA chains formed entanglements with cellulose chains, which required a greater force to destroy the composite fiber structure during stretching. From Fig. 6 (b), it can be seen that the elongation at break of the fiber increases with the increase of PVA, which is mainly because the polyvinyl alcohol molecular structure contains a large number of hydroxyl structures, and these hydroxyl groups can interact with each other through hydrogen bonding to form a three-dimensional network structure of polyvinyl alcohol molecular chains, which makes the polyvinyl alcohol molecules have better flexibility, and when regenerated cellulosic fibers are added to PVA, the regenerated Moreover, when the regenerated cellulose fiber is added with PVA, the macromolecular chain in cellulose forms entanglement with PVA, which increases the elasticity in the process of stretching, so the elongation at break of the blended fiber increases. 3.5 Water-resistant In order to test the water resistance of the hybrid fibers, RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 were placed in boiling water at 97 ℃ for 1 h, dried at 70 ℃ to constant weight, and subjected to a weight loss test and SEM images to observe the changes in morphology. The results showed that the weight loss of RCF-5 was 3.5%, RCF-5 was 4.7%, RCF-10 was 6.2%, and RCF-15 was 7.5%. The weight loss of RCF could be the debris on the surface of the hybrid fiber, and the weight loss of the hybrid fiber also included the loss of PVA, but the PVA was not completely lost. From the SEM image Fig. 7 , the morphology of 0% PVA content and 5% PVA did not change much before and after boiling. The study shows that polyvinyl alcohol will dissolve in water in aqueous solution at 95°C. However, the hybrid fiber will increase the orientation of the fiber during spinning and stretching, and the cellulose and polyethanol will form hydrogen bonding, which will reduce the hydrophilic groups on polyvinyl alcohol, so that the water resistance of polyvinyl alcohol will be improved in the hybrid fiber. The polyvinyl alcohol in the hybrid fiber has a certain water washing resistance as observed by the washing quality change and morphology. Of course, there are many cellulose in textile cellulose that are also not washable at high temperature, such as silk, down, wool and so on. This problem provides help for us to improve the blended fibers in the future, and for this problem, the water resistance can be improved by chemical modification of PVA(Baloyi, Sithole & Chunilall, 2024 ; Park et al., 2019 ). 3.5. Dyeing properties of regenerated cellulose-polyvinyl alcohol blend fibers Natural dyes are derived from nature, are environmentally friendly and are not harmful to human health. Tea-derived natural dyes not only give a more friendly feeling, but also have a promising future in the textile field. In order to increase the application range of RC/PVA enhanced co-blended fibers, this study dyed the co-blended fibers with pigments extracted from Pu-erh tea and observed and analyzed the dyeing effect. In measuring the color of the samples, a colorimeter was used to obtain their Lab and K/S values.Lab values are three basic coordinates in the color space that represent luminance ( L* ), red-green difference ( a* ), and yellow-blue difference ( b* ), respectively. These three values are obtained by comparing the difference between the color of an object and a standard color. K/S is usually used to indicate the degree of color depth on the surface of a solid specimen, i.e., the concentration of a colored substance. The K/S and L* , a* , b* of RC/PVA-enhanced co-blended fibers stained with pigments extracted from Pu-erh tea are shown in Table 1 , and the K/S of RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 were 4.05, 4.34, 4.50, and 4.58, respectively, before washing. With the increase of PVA in the enhanced co-blended fibers, the K/S and L* , a* , and b* values of enhanced co-blended cellulose were increased after staining. K/S and L* , a* , b* values of the blended cellulose increased and the color of the cellulose became darker. The color of RCF/PVA-15 was brown due to the brown color of tea extract pigment and the brown color of pure cellulose fibers after dyeing. This is mainly due to the fact that with the increase of PVA, there are more hydroxyl groups in the blended fibers, which can form more hydrogen bonds with the phenolics in the natural pigments. After washing, the K/S values of RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 were 3.53, 4.02, 4.16, and 4.25, respectively, which were lower than those of K/S and L* , a* , and b* before soaping, which was mainly due to the removal of the tea pigment from the surface of the fibers during the soaping process, but RC/PVA still had a better dyeing effect after soaping. However, RC/PVA still has better dyeing effect after soaping. Therefore, the dyeing performance of RC/PVA reinforced co-blended fibers was better than that of cellulose regenerated fibers for the extracted pigments of Pu-erh tea. Table 1 L* , a* , b* values of regenerated cellulose fibers with different PVA contents before and after washing Sample Before washing After washing L * a * b * K/S L * a * b * K/S 0 45.01 6.63 10.08 4.05 48.08 5.94 10.36 3.53 5 42.29 6.88 8.61 4.34 44.25 5.74 8.46 4.02 10 41.18 6.43 7.48 4.50 42.53 5.38 7.22 4.16 15 38.91 5.06 4.70 4.58 42.37 6.00 7.19 4.25 4. CONCLUSIONS This paper demonstrates a method to extract cellulose from waste cotton using ionic liquids and dimethyl sulfoxide and prepare RCF/PVA fibers by wet spinning. Low-cost waste cotton was used as the raw material. The dissolution method using a blend of ionic liquid and dimethyl sulfoxide has the advantages of simple process and recyclability. Compared with RCF, the mechanical properties of RCF/PVA composite fibers were improved; it was observed by SEM plots that with the increase of PVA content, the indication of RCF/PVA was gradually glossy; thermogravimetric tests showed that the residue amount of RCF/PVA-15 would be reduced from 21.4% of RCF to 0.1% at 700 ℃, and there was also a significant RCF/PVA at 550 ℃ The thermal decomposition phenomenon of RCF/PVA at 550 ℃ indicates that the thermal stability of RCF/PVA has been improved. In addition, RCF/PVA has better dyeing performance than cellulose fibers in pu-erh tea extract pigment dyeing, and dyeing with pu-erh tea extract pigment has a rich source and also reduces the pollution to the environment. The preparation of RCF/PVA by using waste cotton is not only the reuse of renewable resources, but also reduces the pollution to the environment, and RCF/PVA provides a new type of fiber for textile materials, which has a good development prospect. Declarations Competing Interests The authors have no relevant financial or non-financial interests to disclose. Auther Contributions All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Hui Zhao, Lili Meng, Menglei Liu, and Lixia Jia. The first draft of the manuscript was written by Linlin Wang and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Ethics approval and consent to participate This paper does not involve any human or animal experiments. Not applicable. Funding This work was supported by the Research and Demonstration of Key Technologies for Deep Treatment and Reuse of Recovered Brine and Dyes (2022B01045-4) Author Contribution All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Hui Zhao, Lili Meng, Menglei Liu, and Lixia Jia. 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Cellulose, 31 (3), 1773-1785. https://doi.org/10.1007/s10570-023-05726-3 Gu, M., Jiang, C., Liu, D., Prempeh, N. & Smalyukh, I. I. (2016). Cellulose Nanocrystal/Poly(ethylene glycol) Composite as an Iridescent Coating on Polymer Substrates: Structure-Color and Interface Adhesion. ACS applied materials & interfaces, 8 (47), 32565-32573. https://doi.org/10.1021/acsami.6b12044 Haule, L. V., Michael Carr, C. & Rigout, M. (2015). Investigation into the removal of a formaldehyde-free easy care cross-linking agent from cotton and the potential for subsequent regeneration of lyocell-type fibres. The Journal of The Textile Institute, 107 (1), 23-33. https://doi.org/10.1080/00405000.2014.1000013 Huang, Z., Tong, A., Xing, T., He, A., Luo, Y., Zhang, Y., … Xu, W. (2024). A triple-crosslinking strategy for high-performance regenerated cellulose fibers derived from waste cotton textiles. International Journal of Biological Macromolecules, 264 . https://doi.org/10.1016/j.ijbiomac.2024.130779 Ishida, T. (2020). Theoretical Investigation of Dissolution and Decomposition Mechanisms of a Cellulose Fiber in Ionic Liquids. The Journal of Physical Chemistry B, 124 (15), 3090-3102. https://doi.org/10.1021/acs.jpcb.9b11527 Jarvis, M. C. (2017). Structure of native cellulose microfibrils, the starting point for nanocellulose manufacture. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 376 (2112). https://doi.org/10.1098/rsta.2017.0045 Ma, Y., Nasri-Nasrabadi, B., You, X., Wang, X., Rainey, T. J. & Byrne, N. (2020). Regenerated Cellulose Fibers Wetspun from Different Waste Cellulose Types. Journal of Natural Fibers, 18 (12), 2338-2350. https://doi.org/10.1080/15440478.2020.1726244 Mqoni, N., Singh, S., Bahadur, I., Hashemi, H. & Ramjugernath, D. (2022). Ionic liquids, the mixture of ionic liquids and their co-solvent with N, N-dimethylformamide as solvents for cellulose using experimental and COSMO study. Results in Engineering, 15 . https://doi.org/10.1016/j.rineng.2022.100484 Nasri-Nasrabadi, B. & Byrne, N. (2020). Converting waste textiles into highly effective sorbent materials. RSC Adv, 10 (62), 37596-37599. https://doi.org/10.1039/d0ra04616g Park, Y., You, M., Shin, J., Ha, S., Kim, D., Heo, M. H., … Seol, J. H. (2019). Thermal conductivity enhancement in electrospun poly(vinyl alcohol) and poly(vinyl alcohol)/cellulose nanocrystal composite nanofibers. Scientific Reports, 9 (1). https://doi.org/10.1038/s41598-019-39825-8 Pereira, C., Pinto, T. V., Santos, R. M. & Correia, N. (2024). Sustainable and Naturally Derived Wet Spun Fibers: A Systematic Literature Review. Fibers, 12 (9). https://doi.org/10.3390/fib12090075 Ren, F., Wang, J., Yu, J., Zhong, C., Xie, F. & Wang, S. (2021). Dissolution of Cellulose in Ionic Liquid–DMSO Mixtures: Roles of DMSO/IL Ratio and the Cation Alkyl Chain Length. ACS Omega, 6 (41), 27225-27232. https://doi.org/10.1021/acsomega.1c03954 Rosson, L. & Byrne, N. (2022). Bicomponent regenerated cellulose fibres: retaining the colour from waste cotton textiles. Cellulose, 29 (7), 4255-4267. https://doi.org/10.1007/s10570-022-04530-9 Ruiz-Caldas, M.-X., Carlsson, J., Sadiktsis, I., Jaworski, A., Nilsson, U. & Mathew, A. P. (2022). Cellulose Nanocrystals from Postconsumer Cotton and Blended Fabrics: A Study on Their Properties, Chemical Composition, and Process Efficiency. ACS Sustainable Chemistry & Engineering, 10 (11), 3787-3798. https://doi.org/10.1021/acssuschemeng.2c00797 Salama, A. & Hesemann, P. (2020). Recent Trends in Elaboration, Processing, and Derivatization of Cellulosic Materials Using Ionic Liquids. ACS Sustainable Chemistry & Engineering, 8 (49), 17893-17907. https://doi.org/10.1021/acssuschemeng.0c06913 Sarker, F., Karim, N., Afroj, S., Koncherry, V., Novoselov, K. S. & Potluri, P. (2018). High-Performance Graphene-Based Natural Fiber Composites. ACS applied materials & interfaces, 10 (40), 34502-34512. https://doi.org/10.1021/acsami.8b13018 Shaghaleh, H., Xu, X. & Wang, S. (2018). Current progress in production of biopolymeric materials based on cellulose, cellulose nanofibers, and cellulose derivatives. RSC Advances, 8 (2), 825-842. https://doi.org/10.1039/c7ra11157f Shamsuri, A. A., Abdan, K. & Jamil, S. N. A. M. (2021). Properties and applications of cellulose regenerated from cellulose/imidazolium-based ionic liquid/co-solvent solutions: A short review. e-Polymers, 21 (1), 869-880. https://doi.org/10.1515/epoly-2021-0086 Sharma, R., Verma, B., Kumar, S., Gupta, A., Sahu, P. K., Singh, P. & Kumar, V. (2022). Recent updates on applications of ionic liquids (ILs) for biomedical sciences. Journal of the Iranian Chemical Society, 19 (8), 3215-3228. https://doi.org/10.1007/s13738-022-02544-5 Shen, H., Sun, T. & Zhou, J. (2023). Recent Progress in Regenerated Cellulose Fibers by Wet Spinning. Macromolecular Materials and Engineering, 308 (10). https://doi.org/10.1002/mame.202300089 Stolarska, O., Pawlowska-Zygarowicz, A., Soto, A., Rodríguez, H. & Smiglak, M. (2017). Mixtures of ionic liquids as more efficient media for cellulose dissolution. Carbohydrate Polymers, 178 , 277-285. https://doi.org/10.1016/j.carbpol.2017.09.025 Sun, X., Wang, X., Sun, F., Tian, M., Qu, L., Perry, P., … Liu, X. (2021). Textile Waste Fiber Regeneration via a Green Chemistry Approach: A Molecular Strategy for Sustainable Fashion. Advanced Materials, 33 (48). https://doi.org/10.1002/adma.202105174 Trilokesh, C., Bavadharani, P., Mahapriyadarshini, M., Janani, R. & Uppuluri, K. B. (2020). Recycling Baby Diaper Waste into Cellulose and Nanocellulose. Waste and Biomass Valorization, 12 (8), 4299-4306. https://doi.org/10.1007/s12649-020-01312-x Verma, C., Mishra, A., Chauhan, S., Verma, P., Srivastava, V., Quraishi, M. A. & Ebenso, E. E. (2019). Dissolution of cellulose in ionic liquids and their mixed cosolvents: A review. Sustainable Chemistry and Pharmacy, 13 . https://doi.org/10.1016/j.scp.2019.100162 Wang, C., Li, Y., Yu, H.-Y., Abdalkarim, S. Y. H., Zhou, J., Yao, J. & Zhang, L. (2021). Continuous Meter-Scale Wet-Spinning of Cornlike Composite Fibers for Eco-Friendly Multifunctional Electronics. ACS applied materials & interfaces, 13 (34), 40953-40963. https://doi.org/10.1021/acsami.1c12012 Wang, Q., Zhao, H., Zhao, L., Huang, M., Tian, D., Deng, S., … Shen, F. (2023). Fabrication of regenerated cellulose fibers using phosphoric acid with hydrogen peroxide treated wheat straw in a DMAc/LiCl solvent system. Cellulose, 30 (10), 6187-6201. https://doi.org/10.1007/s10570-023-05263-z Wu, H., Wang, B., Li, T., Wu, Y., Yang, R., Gao, H. & Nie, Y. (2023). Efficient recycle of waste poly-cotton and preparation of cellulose and polyester fibers using the system of ionic liquid and dimethyl sulfoxide. Journal of Molecular Liquids, 388 . https://doi.org/10.1016/j.molliq.2023.122757 Xie, X., Hong, Y., Zeng, X., Dai, X. & Wagner, M. (2021). A Systematic Literature Review for the Recycling and Reuse of Wasted Clothing. Sustainability, 13 (24). https://doi.org/10.3390/su132413732 Yi, T., Zhao, H., Mo, Q., Pan, D., Liu, Y., Huang, L., … Song, H. (2020). From Cellulose to Cellulose Nanofibrils—A Comprehensive Review of the Preparation and Modification of Cellulose Nanofibrils. Materials, 13 (22). https://doi.org/10.3390/ma13225062 Zainul Armir, N. A., Zulkifli, A., Gunaseelan, S., Palanivelu, S. D., Salleh, K. M., Che Othman, M. H. & Zakaria, S. (2021). Regenerated Cellulose Products for Agricultural and Their Potential: A Review. Polymers, 13 (20). https://doi.org/10.3390/polym13203586 Zhao, Z., Gao, H., Zhou, L., Wang, J., Yuan, H., Wei, J., … Nie, Y. (2023). Preparation of regenerated cellulose fibers by microfluidic spinning technology using ionic liquids as the solvents. Cellulose, 30 (12), 7535-7549. https://doi.org/10.1007/s10570-023-05301-w Zhou, Y., Zhang, X., Yin, D., Zhang, J., Mi, Q., Lu, H., … Zhang, J. (2022). The solution state and dissolution process of cellulose in ionic-liquid-based solvents with different hydrogen-bonding basicity and microstructures. Green Chemistry, 24 (9), 3824-3833. https://doi.org/10.1039/d2gc00374k Zhou, Z., Yao, Y., Zhang, J., Shen, L., Xu, H., Liu, J. & Shentu, B. (2022). Effects of poly(vinyl alcohol) (PVA) concentration on rheological behavior of TEMPO-mediated oxidized cellulose nanofiber/PVA suspensions. Cellulose, 29 (15), 8255-8263. https://doi.org/10.1007/s10570-022-04786-1 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 23 Jan, 2026 Read the published version in Cellulose → Version 1 posted Editorial decision: Revision requested 31 Oct, 2024 Reviews received at journal 29 Oct, 2024 Reviews received at journal 20 Oct, 2024 Reviewers agreed at journal 17 Oct, 2024 Reviewers agreed at journal 16 Oct, 2024 Reviewers agreed at journal 16 Oct, 2024 Reviewers invited by journal 16 Oct, 2024 Editor assigned by journal 14 Oct, 2024 Submission checks completed at journal 30 Sep, 2024 First submitted to journal 29 Sep, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5173409","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":375301028,"identity":"ad620210-cfdd-45c4-9ecb-756391091da2","order_by":0,"name":"Linlin Wang","email":"","orcid":"","institution":"Xinjiang University","correspondingAuthor":false,"prefix":"","firstName":"Linlin","middleName":"","lastName":"Wang","suffix":""},{"id":375301029,"identity":"565bc16f-36f2-4156-a284-843bf1d65dae","order_by":1,"name":"Hui Zhao","email":"","orcid":"","institution":"Fiber Inspection Institute of Hui Autonomous 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07:08:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5173409/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5173409/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s10570-026-06945-0","type":"published","date":"2026-01-23T15:58:32+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":68909652,"identity":"e2a732a6-dc2a-4987-921f-21b8d4cd2315","added_by":"auto","created_at":"2024-11-13 11:26:48","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":84213,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of RCF/PVA preparation\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5173409/v1/d8ea02b70f5a9fdff8cdad20.png"},{"id":68908729,"identity":"3ae5b042-145d-4d19-93c8-a021df32e564","added_by":"auto","created_at":"2024-11-13 11:18:48","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":325174,"visible":true,"origin":"","legend":"\u003cp\u003eSurface and cross-section SEM images of (a, b, c) RCF, (d, e, f) RCF/PVA-5, (g, h, i) RCF/PVA-10, (j, k, l) RCF/PVA-15\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5173409/v1/90c2bc2cc29bcf62e982dc1c.png"},{"id":68909655,"identity":"6040c9cc-951f-4e25-9df1-a0ca6a80be96","added_by":"auto","created_at":"2024-11-13 11:26:49","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":72944,"visible":true,"origin":"","legend":"\u003cp\u003eFT-IR plots of RCF, RCF/PVA-5, RCF/PVA-10, RCF/PVA-15\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5173409/v1/411906f3574d090e745f7203.png"},{"id":68909653,"identity":"8da3440d-cf59-4473-af29-eb05bf76c15a","added_by":"auto","created_at":"2024-11-13 11:26:48","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":73744,"visible":true,"origin":"","legend":"\u003cp\u003eXRD patterns of RCF, RCF/PVA-5, RCF/PVA-10, RCF/PVA-15\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5173409/v1/1091a3b304dfdc595d3caab6.png"},{"id":68908734,"identity":"7b475386-e5a0-44b4-945f-070a12608a40","added_by":"auto","created_at":"2024-11-13 11:18:49","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":62406,"visible":true,"origin":"","legend":"\u003cp\u003eTG-DTG plots for RCF, RCF/PVA-5, RCF/PVA-10, RCF/PVA-15\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5173409/v1/e839e0b99e0cea9e1de5a8aa.png"},{"id":68908732,"identity":"08783694-b481-46c3-97fa-e714e17c10e6","added_by":"auto","created_at":"2024-11-13 11:18:49","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":27335,"visible":true,"origin":"","legend":"\u003cp\u003eMechanical properties of RCF, RCF/PVA-5, RCF/PVA-10, RCF/PVA-15.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-5173409/v1/58c754ecf6a311b0778b1ca6.png"},{"id":68908727,"identity":"4efa4959-dc8d-4e92-9663-4cab7cc3eb2e","added_by":"auto","created_at":"2024-11-13 11:18:48","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":249588,"visible":true,"origin":"","legend":"\u003cp\u003eRCF(a, b), RCF/PVA-5(c, d) , RCF/PVA-10(e, f) , RCF/PVA-15(g, h) SEM images of surface and cross-section after high temperature washing\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-5173409/v1/d6f927cdf068782ed8a1e9fd.png"},{"id":101151926,"identity":"6aeb1124-e79c-4415-8152-c29882612037","added_by":"auto","created_at":"2026-01-26 16:08:22","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1752349,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5173409/v1/4b65090e-1a15-4917-98ce-9fb3f52c03ba.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Preparation of recycled cellulose-polyvinyl alcohol reinforced co-blended fibers based on waste cotton","fulltext":[{"header":"1. INTRODUCTION","content":"\u003cp\u003eAt present, the global development of energy and its related industries has gradually formed a trend of low carbon. According to the requirements of carbon peak and carbon neutrality goals, a green low-carbon circular development economic system will be initially formed in 2025, and the proportion of non-fossil energy consumption will reach about 20%. As a green, renewable and recyclable resource, cellulose is of great significance to achieve carbon peak and carbon neutrality by rationally using cellulose instead of non-renewable resources(Acharya et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Dorugade et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Garces, Ngo, Ayranci \u0026amp; Boluk, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Jarvis, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Sarker et al., \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Shaghaleh, Xu \u0026amp; Wang, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Zainul Armir et al., \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Cotton fiber is an important textile raw material, the total amount of fiber processing in China is about 50\u0026nbsp;million tons per year, and the generated waste textiles is about 20\u0026nbsp;million tons, while the comprehensive utilization rate of waste textiles is only 15%, and the recycling capacity and level of waste textiles still have greater room for improvement. Therefore the recycling of waste cotton textiles not only reduces the pollution of the environment, but also improves the reuse of resources(Chang, Kao, Chen, Zhang \u0026amp; Wu, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Nasri-Nasrabadi \u0026amp; Byrne, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Rosson \u0026amp; Byrne, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Wu et al., \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Xie, Hong, Zeng, Dai \u0026amp; Wagner, \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). At present, for the recycling of waste cotton textiles are mainly physical and chemical methods. Burial or incineration is not only a waste of resources but also pollutes the environment(Sun et al., \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; C. Wang et al., \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Mechanical crushing method, not conducive to the extraction of blended or interwoven fibers, which also greatly limits the scope of application(Ruiz-Caldas et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Trilokesh, Bavadharani, Mahapriyadarshini, Janani \u0026amp; Uppuluri, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Yi et al., \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Chemical method is to use the solvent to dissolve the fiber for regeneration, but there are problems of low dissolution efficiency or solvent recontamination(Q. Cheng et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; X.-W. Cheng, Tang, Yao \u0026amp; Yang, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Gu, Jiang, Liu, Prempeh \u0026amp; Smalyukh, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Ishida, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe main problem with the reuse of cellulose is that cellulose is neither water-soluble nor soluble in general organic solvents, due to the presence of hydrogen bonds between cellulose molecules. The full use of cellulose needs to destroy the hydrogen bonds between and within the cellulose molecules. At present, the methods of chemical preparation of waste cotton fabric into reclaimed cellulose fiber mainly include cuprammonium method(Shen, Sun \u0026amp; Zhou, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), Sodium hydroxide/urea/thiourea method(El Bouazzaoui, Habsaoui \u0026amp; Touhami, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2022\u003c/span\u003e), LiCl/DMAc method(Q. Wang et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), N-methylmorph oxide (NMMO) solvent method and ionic liquid method(Haule, Michael Carr \u0026amp; Rigout, 2015; Zhao et al., \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Although cupramine solution is recyclable, corrosive substances need to be added in the process of preparing reclaimed cellulose fiber from cupramine solution. Will cause pollution to the environment; LiCl/DMAc method has high cost, low efficiency and pollution to the environment. In the N-methylmorpholine oxide (NMMO) solvent method, NMMO is prone to discoloration and decomposition explosion under high temperature conditions. Ionic liquid has become a hot research field in preparing regenerated cellulose due to its high thermal stability, chemical stability and recyclability.\u003c/p\u003e \u003cp\u003eIonic liquids have the advantages of recyclability and non-pollution, which have become the hotspot of recent research in various fields(Huang et al., \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Salama \u0026amp; Hesemann, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Shamsuri, Abdan \u0026amp; Jamil, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Sharma et al., \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Studies have shown that adding specific aprotic solvents to ionic liquids can effectively improve the dissolution effect of cellulose, and aprotic solvents will make cellulose swell, which can effectively promote the ionic liquid into the cellulose interior(El Seoud, Bioni \u0026amp; Dignani, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Ma et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Mqoni, Singh, Bahadur, Hashemi \u0026amp; Ramjugernath, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Ren et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Stolarska, Pawlowska-Zygarowicz, Soto, Rodr\u0026iacute;guez \u0026amp; Smiglak, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Verma et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Y. Zhou et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). However, the resulting regenerated cellulose suffers from poor mechanical properties(Pereira, Pinto, Santos \u0026amp; Correia, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Therefore, Zhuo Cao co-dissolved cellulose and polyacrylonitrile in ionic liquid, and wet-spun to improve the mechanical properties of the regenerated cellulose fiber, but the polyacrylonitrile had the defect of alkali resistance(Azimi et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Cao, Li, Suo, Liu \u0026amp; Lu, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Yuhui Ci spun a composite fiber with good mechanical properties by dissolving cellulose and thermoplastic polyurethane (TPU) at the same time to provide a feasible method for the study of composite materials(Ci, Lv, Yang, Du \u0026amp; Tang, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Among many polymers, polyvinyl alcohol (PVA) is a biodegradable green polymer compound with good fiber-forming properties, tensile strength, good resistance to chemicals and corrosion, and polyvinyl alcohol rich in hydroxyl structure can be very good compatibility with cellulose, and textile fibers in the vinylon is a synthetic fiber spun from PVA as raw material(Z. Zhou et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Therefore, the recycled cellulose-polyvinyl alcohol blended fibers were prepared by wet spinning technology using low-cost waste indigo denim cotton yarn as raw material, and dissolving waste cotton and polyvinyl alcohol into spinning solution using [Bmim]Cl/DMSO. In addition, the regenerated cellulose fibers and regenerated cellulose/poly(vinyl alcohol)-enhanced co-blended fibers were dyed using Pu-erh tea extract to investigate the dyeing performance of the enhanced co-blended fibers with different PVA contents on the natural dyes extracted from Pu-erh tea.\u003c/p\u003e"},{"header":"2. EXPERIMENTAL","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Materials\u003c/h2\u003e \u003cp\u003e1-butyl-3-methylimidazole chloride ([Bmim]Cl), dimethyl sulfoxide (DMSO) and polyvinyl alcohol (PVA) were purchased from Shanghai Ala Liability Co., LTD. N, N-dimethylformamide and sodium hydroxide were purchased from Tianjin Zhiyuan Chemical Reagent Co., LTD., hydrogen peroxide was purchased from Tianjin Yongsheng Fine Chemical Co., LTD., insurance powder was purchased from Tianjin Damao Chemical Reagent Factory, methanol was purchased from Tianjin Xinbaite Chemical Co., LTD. Deionized water (16.8 MΩ\u0026middot;cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, Millipore Milli-Q) made in the lab.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2. Dissolving the Waste Cotton\u003c/h2\u003e \u003cp\u003eWaste indigo cotton yarns were sterilized and washed using aqueous hydrogen peroxide (1 wt%) and then dried to be decolorized. Accurately measure 300 mL of N,N-dimethylmethylamine was transferred to a 1000 mL volumetric flask, accurately weigh 9 g of NaOH and 10 g of Na\u003csub\u003e2\u003c/sub\u003eS\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e were added to the volumetric flask, and the volume was fixed with distilled water, and then shaken well as the stripping solution for use. In the sufficient amount of NaOH and Na\u003csub\u003e2\u003c/sub\u003eS\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e, the indigo dyed on the fibers were all reduced to yellow soluble cryptochrome salts, and under the adsorption and solubilizing effect of the stripping solution, the cryptochrome salts dissolved into DMF. Under the adsorption and solubilization effect of the color stripping solution, the cryptochrome salt was dissolved into DMF solution. Accurately weigh 0.2 g of baked dyed cotton yarn in a beaker, add 50 mL of color stripping solution to it, put it in a 70 ℃ water bath at a constant temperature to strip the color for 15 min, then wash, dry, and cut into pieces. Put 0.2 g of stripped cotton into the DMSO/B(mim)Cl mixed solution (molar ratio of 1:1), heat up to 120 ℃ and add 5%, 10%, 15% of the cotton mass of PVA, mechanical stirring for 4 h, followed by the obtained homogeneous spinning solution.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3. Preparation of regenerated cellulose and polyvinyl alcohol blend fiber\u003c/h2\u003e \u003cp\u003eThe spinning liquid was placed in a syringe and peristaltic pumped at 8 ml/h, extruded through a 1 mm diameter exit hole, stretched and then solidified in a methanol coagulation bath at 20 ℃. After the methanol bath through the winding device collection (take cellulose samples with silver nitrate solution to detect the presence of ionic liquids, if there is no white precipitate produced, it is proved that the ionic liquids in the hybrid fibers are removed), natural drying to obtain regenerated cellulose - polyvinyl alcohol co-blended fibers, the preparation process shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The blended fibers with PVA mass ratio of 0%, 5%, 10% and 15% were named RCF, RCF/PVA-5, RCF/PVA-10 and RCF/PVA-15, respectively.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4. Dyeing of the Extracted Process\u003c/h2\u003e \u003cp\u003ePu-erh tea extract pigment: weigh 25 g of Pu-erh tea, immersed in a round-bottomed flask containing 150 ml of deionized water, placed in a water bath and heated to 95 ℃, kept warm for 60 min, filtered the tea residue, the extract was used as a dye solution for use. Dyeing process: take 100 ml of dye solution in a beaker, add 0.1 g citric acid, heating to 40 ℃, respectively, will be different types of 2 g co-blended fibers added to the dye solution after heating, heating rate of 2 ℃ / min, when the temperature reaches 90 ℃, insulation 50 min, and then cool down the temperature of the water washing and drying, will be dyed cellulose to be measured. After dyeing the composite fiber in 2g / L soap flake solution to 49 ℃, stirring 1h after drying to be measured.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.5. Characterization\u003c/h2\u003e \u003cp\u003eMorphology measurements\u003c/p\u003e \u003cp\u003eHigh resolution field emission scanning electron microscopy (JSM-7610F Plus Japan) was used to observe the fiber display and cross section. The fiber cross section sample was obtained by the Haber slicer, the fiber sample was fixed on the sample table with conductive adhesive, and then the sample was sprayed with gold for 120 s, and analyzed under the accelerated voltage of 5.0 KV. The SEM images of fiber surface and cross section with different multiples were obtained.\u003c/p\u003e \u003cp\u003eChemical structure characterization\u003c/p\u003e \u003cp\u003eIn order to observe whether the mixed fiber contains PVA, Fourier transform infrared spectrometer (FTIR Vertical-70-RAMI Japan) was used to test the fiber. The fiber was dried in a constant temperature oven at 80 ℃ for 12 h, and then crushed to obtain the sample. The sample was prepared by KBr tablet. The scanning accuracy is 4 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and the scanning range is 400 to 4000 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eCrystallinity analysis\u003c/p\u003e \u003cp\u003eIn order to observe the crystal change of the mixed fiber, X-ray powder diffractometer (Bruker D8 Advance Germany) was used to test the fiber, using CuKa target, X-ray wavelength of 1.5405A, scanning Angle range of 5\u0026ndash;60 \u0026deg;, speed of 8 \u0026deg;/min, operating voltage of 40 kV, current of 25 mA.The XRD patterns had been smoothed by MDI Jade and carried out with Origin software.\u003c/p\u003e \u003cp\u003eThermal stability analysis\u003c/p\u003e \u003cp\u003eThe thermal stability of the fibers was tested using a thermogravimetric-differential thermal thermal analyzer (TG-DTG HITACHI STA7300, Japan) with a temperature increase rate of 15 ℃/min and an airflow rate of 200 ml/min to 700\u0026deg;C. The TG-DTG plots of the aerogels were obtained.\u003c/p\u003e \u003cp\u003eMechanical properties measurements\u003c/p\u003e \u003cp\u003eThe breaking strength and tensile strength of fibers can be obtained by testing the mechanical properties of fibers with a strength meter ( 008E China). The test temperature was 30 ℃, the humidity was 30%, the fiber holding length was 50 mm, and the stretching rate was 10 mm/min. Each cellulose sample was repeated for 12 times, and the results were averaged.\u003c/p\u003e \u003cp\u003eColor measurements\u003c/p\u003e \u003cp\u003eThe \u003cem\u003eK/S\u003c/em\u003e values, Obtained by spectrophotometer(Ultra Scan PRO, Hunter Lab, USA) CIE \u003cem\u003eL* a* b* C*\u003c/em\u003eand \u003cem\u003eh\u003c/em\u003e\u003csup\u003e\u003cem\u003eo\u003c/em\u003e\u003c/sup\u003e coordinates were obtained using a Datacolor 850 spectrophotometer, which includes UV and specular components and utilizes illuminant D65 and 10 \u003csup\u003eo\u003c/sup\u003e standard observer) .\u003c/p\u003e \u003c/div\u003e"},{"header":"3. RESULTS AND DISCUSSION","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.1. Morphological characteristics of regenerated cellulose-polyvinyl alcohol blended fibers\u003c/h2\u003e \u003cp\u003eIn order to observe the apparent phenomena of the fibers after spinning, the cellulose was observed by scanning electron microscopy.The morphological characteristics of RCF and RCF/PVA composite fibers are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, from which it can be seen that the diameter of the fibers is about 100\u0026ndash;120 \u0026micro;m, and that the diameter of RCF is larger than that of RCF/PVA, and the diameter of RCF/PVA decreases gradually with the increase of PVA content. From Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e (a-c), it can be seen that the surface of RCF is relatively smooth, without cracks and grooves, and no hollow phenomenon was found from the cross-section, which indicates that solvent substitution of RCF in the solidification bath did not have too much effect on the surface morphology of the fibers. From Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e (d-l), it can be seen that with the increase of PVA content, the surface of the fibers with cracks and grooves on the surface gradually showed relatively smooth, which may be caused by the different rates of solvent substitution between cellulose and PVA in the solidification bath of RCF/PVA. The cross-section showed cracks in the fibers but not hollow, which may be due to the deformation of the fibers under external forces when using a haft slicer, resulting in deformation of the cross-section. The co-blended fibers were observed by SEM to be fibre-forming and could satisfy the spinnability.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.2. Chemical structure of regenerated cellulose-polyvinyl alcohol blend fiber\u003c/h2\u003e \u003cp\u003eThe chemical structure information of RCF and RCF/PVA was obtained using FT-IR spectroscopy, and the IR spectral information is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. The absorption peak of RCF near 3400 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e is the telescopic vibrational peak of -OH, and the characteristic peaks of -CH in cellulose are at around 2900 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, the bending vibrational peak of -CH at around 1426 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and the C-O at around 1156 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. -C asymmetric stretching vibration peak. The formed RCF/PVA retains the characteristic peak of cellulose, the absorption peak of -OH is shifted to 3355 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e due to hydrogen bonding, the absorption peak around 3200 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e retains the -OH absorption peak of PVA, and the characteristic peak around 2900 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e is the -CH-symmetric telescoping vibration peak of cellulose and PVA. From the FT-IR spectra, it can be obtained that the chemical structure of cellulose did not change after the ionic liquid treatment, and the mixed fibers contained PVA, which was not lost in the solidification bath.\u003c/p\u003e \u003cp\u003eIn order to further verify the crystalline structure of the prepared RCF/PVA, XRD analysis of RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 was carried out using X-ray diffractometer. As can be seen in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, the diffraction peak of RCF at 2θ of 20.8 corresponds to the cellulose type II crystal type, indicating that the cellulose in the waste cotton was transformed from cellulose type I to cellulose type II in the ionic liquid co-solvent solubilization. The prepared RCF/PVA showed a new diffraction peak at 22.4, which is a unique diffraction peak of PVA. From the figure, we can see that the diffraction peak at 22.4 is not very obvious, on the one hand, it is because cellulose and PVA precipitated in the solidification bath in the process of cellulose and PVA chain entanglement phenomenon, and on the other hand, it is because of the addition of a smaller amount of PVA, in the X-ray did not appear obvious diffraction peaks. The diffraction peaks appeared obviously under X-ray. In terms of crystallinity, the crystallinity of RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 were 46%, 51.6%, 61.9%, and 67.9%, respectively, and the crystallinity of the mixed cellulose increased with the increase of PVA content.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.3. Thermal stability of regenerated cellulose-polyvinyl alcohol blend fiber\u003c/h2\u003e \u003cp\u003eThe thermal stability of RCF and RCF/PVA in air was investigated by thermogravimetric method, and the TG and DTG curves of RCF and RCF/PVA are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. As can be seen from the figure, with the rise in temperature RCF weight loss is mainly divided into two stages, the first stage is below 150 ℃, in the stage RCF is mainly water volatilization; the second stage is between 150\u0026ndash;600 ℃, in the stage of the maximum rate of thermal decomposition temperature of 328 ℃, the stage of the decomposition of cellulose to produce CO\u003csub\u003e2\u003c/sub\u003e and water, with the evaporation of CO\u003csub\u003e2\u003c/sub\u003e and water the weight of the larger changes in the weight, mainly for cellulose thermal cracking. The weight of RCF was basically stable after 600 ℃, and the residual carbon at 700 ℃ was 21.4%. Preparation of RCF/PVA in the heat process there are mainly three stages of weight loss, the first stage is below 150 ℃, in the stage is mainly in line with the volatilization of water in the fiber, the second stage is 150\u0026ndash;400 ℃, in the stage of thermal decomposition is mainly cellulose decomposition of CO\u003csub\u003e2\u003c/sub\u003e and water, while the PVA generates water, acetic acid, acetaldehyde, etc.; the third stage is 400\u0026ndash;600 ℃, in the stage of composite fibers is mainly decomposed into acetaldehyde. The third stage is 400\u0026ndash;600 ℃, in this stage is mainly the composite fiber PVA decomposition into acetic acid, acetaldehyde, etc. continue to decompose into CO\u003csub\u003e2\u003c/sub\u003e and water. 600 ℃ after the weight of RCF is basically stable, and the residual carbon of RCF/PVA-5 at 700 ℃ is 0.1%, which is mainly due to the purity of PVA is very high, will be decomposed into CO\u003csub\u003e2\u003c/sub\u003e and water completely after reaching a certain temperature. While the residual carbon-carbon bond aromatization of cellulose after a certain temperature eventually forms charcoal, levogluconic anhydride condensation to form levoglucose further forms a liquid mixture of wood tar, and impurities in the cellulose also remain in the residual carbon(Fan et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e3.4. Mechanical properties of regenerated cellulose-polyvinyl alcohol blend fibers\u003c/h2\u003e \u003cp\u003eRegenerated cellulose fibers have good breaking strength but low elongation due to high crystallinity and regular molecular arrangement in the fibers. Therefore, the effects of different polyvinyl alcohol additions on the mechanical properties of regenerated cellulose fibers were explored, and the tensile strength and elongation at break of RCF and RCF/PVA are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e(a). The tensile strength of the blended fibers increased with the increase of PVA content, mainly because PVA formed more hydrogen bonds with cellulose, while the PVA chains formed entanglements with cellulose chains, which required a greater force to destroy the composite fiber structure during stretching. From Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e(b), it can be seen that the elongation at break of the fiber increases with the increase of PVA, which is mainly because the polyvinyl alcohol molecular structure contains a large number of hydroxyl structures, and these hydroxyl groups can interact with each other through hydrogen bonding to form a three-dimensional network structure of polyvinyl alcohol molecular chains, which makes the polyvinyl alcohol molecules have better flexibility, and when regenerated cellulosic fibers are added to PVA, the regenerated Moreover, when the regenerated cellulose fiber is added with PVA, the macromolecular chain in cellulose forms entanglement with PVA, which increases the elasticity in the process of stretching, so the elongation at break of the blended fiber increases.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e3.5 Water-resistant\u003c/h2\u003e \u003cp\u003eIn order to test the water resistance of the hybrid fibers, RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 were placed in boiling water at 97 ℃ for 1 h, dried at 70 ℃ to constant weight, and subjected to a weight loss test and SEM images to observe the changes in morphology. The results showed that the weight loss of RCF-5 was 3.5%, RCF-5 was 4.7%, RCF-10 was 6.2%, and RCF-15 was 7.5%. The weight loss of RCF could be the debris on the surface of the hybrid fiber, and the weight loss of the hybrid fiber also included the loss of PVA, but the PVA was not completely lost. From the SEM image Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e, the morphology of 0% PVA content and 5% PVA did not change much before and after boiling. The study shows that polyvinyl alcohol will dissolve in water in aqueous solution at 95\u0026deg;C. However, the hybrid fiber will increase the orientation of the fiber during spinning and stretching, and the cellulose and polyethanol will form hydrogen bonding, which will reduce the hydrophilic groups on polyvinyl alcohol, so that the water resistance of polyvinyl alcohol will be improved in the hybrid fiber. The polyvinyl alcohol in the hybrid fiber has a certain water washing resistance as observed by the washing quality change and morphology. Of course, there are many cellulose in textile cellulose that are also not washable at high temperature, such as silk, down, wool and so on. This problem provides help for us to improve the blended fibers in the future, and for this problem, the water resistance can be improved by chemical modification of PVA(Baloyi, Sithole \u0026amp; Chunilall, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Park et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2019\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003e3.5. Dyeing properties of regenerated cellulose-polyvinyl alcohol blend fibers\u003c/h2\u003e \u003cp\u003eNatural dyes are derived from nature, are environmentally friendly and are not harmful to human health. Tea-derived natural dyes not only give a more friendly feeling, but also have a promising future in the textile field. In order to increase the application range of RC/PVA enhanced co-blended fibers, this study dyed the co-blended fibers with pigments extracted from Pu-erh tea and observed and analyzed the dyeing effect. In measuring the color of the samples, a colorimeter was used to obtain their Lab and \u003cem\u003eK/S\u003c/em\u003e values.Lab values are three basic coordinates in the color space that represent luminance (\u003cem\u003eL*\u003c/em\u003e), red-green difference (\u003cem\u003ea*\u003c/em\u003e), and yellow-blue difference (\u003cem\u003eb*\u003c/em\u003e), respectively. These three values are obtained by comparing the difference between the color of an object and a standard color. \u003cem\u003eK/S\u003c/em\u003e is usually used to indicate the degree of color depth on the surface of a solid specimen, i.e., the concentration of a colored substance.\u003c/p\u003e \u003cp\u003eThe \u003cem\u003eK/S\u003c/em\u003e and \u003cem\u003eL*\u003c/em\u003e, \u003cem\u003ea*\u003c/em\u003e, \u003cem\u003eb*\u003c/em\u003e of RC/PVA-enhanced co-blended fibers stained with pigments extracted from Pu-erh tea are shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, and the \u003cem\u003eK/S\u003c/em\u003e of RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 were 4.05, 4.34, 4.50, and 4.58, respectively, before washing. With the increase of PVA in the enhanced co-blended fibers, the \u003cem\u003eK/S\u003c/em\u003e and \u003cem\u003eL*\u003c/em\u003e, \u003cem\u003ea*\u003c/em\u003e, and \u003cem\u003eb*\u003c/em\u003e values of enhanced co-blended cellulose were increased after staining. \u003cem\u003eK/S\u003c/em\u003e and \u003cem\u003eL*\u003c/em\u003e, \u003cem\u003ea*\u003c/em\u003e, \u003cem\u003eb*\u003c/em\u003e values of the blended cellulose increased and the color of the cellulose became darker. The color of RCF/PVA-15 was brown due to the brown color of tea extract pigment and the brown color of pure cellulose fibers after dyeing. This is mainly due to the fact that with the increase of PVA, there are more hydroxyl groups in the blended fibers, which can form more hydrogen bonds with the phenolics in the natural pigments. After washing, the \u003cem\u003eK/S\u003c/em\u003e values of RCF, RCF/PVA-5, RCF/PVA-10, and RCF/PVA-15 were 3.53, 4.02, 4.16, and 4.25, respectively, which were lower than those of \u003cem\u003eK/S\u003c/em\u003e and \u003cem\u003eL*\u003c/em\u003e, \u003cem\u003ea*\u003c/em\u003e, and \u003cem\u003eb*\u003c/em\u003e before soaping, which was mainly due to the removal of the tea pigment from the surface of the fibers during the soaping process, but RC/PVA still had a better dyeing effect after soaping. However, RC/PVA still has better dyeing effect after soaping. Therefore, the dyeing performance of RC/PVA reinforced co-blended fibers was better than that of cellulose regenerated fibers for the extracted pigments of Pu-erh tea.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003e\u003cem\u003eL*\u003c/em\u003e, \u003cem\u003ea*\u003c/em\u003e, \u003cem\u003eb*\u003c/em\u003e values of regenerated cellulose fibers with different PVA contents before and after washing\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSample\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eBefore washing\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c9\" namest=\"c6\"\u003e \u003cp\u003eAfter washing\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eL\u003c/em\u003e\u003csup\u003e\u003cem\u003e*\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003ea\u003c/em\u003e\u003csup\u003e\u003cem\u003e*\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eb\u003c/em\u003e\u003csup\u003e\u003cem\u003e*\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eK/S\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eL\u003c/em\u003e\u003csup\u003e\u003cem\u003e*\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003ea\u003c/em\u003e\u003csup\u003e\u003cem\u003e*\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cem\u003eb\u003c/em\u003e\u003csup\u003e\u003cem\u003e*\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cem\u003eK/S\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e45.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e10.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e48.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e5.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e10.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e3.53\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e42.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e8.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e44.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e5.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e8.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e4.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e41.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e7.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e42.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e5.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e7.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e4.16\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e38.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e42.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e6.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e7.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e4.25\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4. CONCLUSIONS","content":"\u003cp\u003eThis paper demonstrates a method to extract cellulose from waste cotton using ionic liquids and dimethyl sulfoxide and prepare RCF/PVA fibers by wet spinning. Low-cost waste cotton was used as the raw material. The dissolution method using a blend of ionic liquid and dimethyl sulfoxide has the advantages of simple process and recyclability. Compared with RCF, the mechanical properties of RCF/PVA composite fibers were improved; it was observed by SEM plots that with the increase of PVA content, the indication of RCF/PVA was gradually glossy; thermogravimetric tests showed that the residue amount of RCF/PVA-15 would be reduced from 21.4% of RCF to 0.1% at 700 ℃, and there was also a significant RCF/PVA at 550 ℃ The thermal decomposition phenomenon of RCF/PVA at 550 ℃ indicates that the thermal stability of RCF/PVA has been improved. In addition, RCF/PVA has better dyeing performance than cellulose fibers in pu-erh tea extract pigment dyeing, and dyeing with pu-erh tea extract pigment has a rich source and also reduces the pollution to the environment. The preparation of RCF/PVA by using waste cotton is not only the reuse of renewable resources, but also reduces the pollution to the environment, and RCF/PVA provides a new type of fiber for textile materials, which has a good development prospect.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eCompeting Interests\u003c/h2\u003e\n\u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\n\u003ch2\u003eAuther Contributions\u003c/h2\u003e\n\u003cp\u003eAll authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Hui Zhao, Lili Meng, Menglei Liu, and Lixia Jia. The first draft of the manuscript was written by Linlin Wang and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003ch2\u003eEthics approval and consent to participate\u003c/h2\u003e\n\u003cp\u003eThis paper does not involve any human or animal experiments. Not applicable.\u003c/p\u003e\n\u003ch2\u003eFunding\u003c/h2\u003e\n\u003cp\u003eThis work was supported by the Research and Demonstration of Key Technologies for Deep Treatment and Reuse of Recovered Brine and Dyes (2022B01045-4)\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eAll authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Hui Zhao, Lili Meng, Menglei Liu, and Lixia Jia. The first draft of the manuscript was written by Linlin Wang and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003ch2\u003eAvailability of data and materials\u003c/h2\u003e\n\u003cp\u003eAll relevant data are authentic and available from the corresponding author upon request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAcharya, S., Liyanage, S., Parajuli, P., Rumi, S. S., Shamshina, J. L. \u0026amp; Abidi, N. (2021). Utilization of Cellulose to Its Full Potential: A Review on Cellulose Dissolution, Regeneration, and Applications. \u003cem\u003ePolymers, 13\u003c/em\u003e(24). https://doi.org/10.3390/polym13244344\u003c/li\u003e\n\u003cli\u003eAzimi, B., Maleki, H., Gigante, V., Bagherzadeh, R., Mezzetta, A., Milazzo, M., \u0026hellip; Danti, S. (2022). Cellulose-based fiber spinning processes using ionic liquids. \u003cem\u003eCellulose, 29\u003c/em\u003e(6), 3079-3129. https://doi.org/10.1007/s10570-022-04473-1\u003c/li\u003e\n\u003cli\u003eBaloyi, R. B., Sithole, B. 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(2022). The solution state and dissolution process of cellulose in ionic-liquid-based solvents with different hydrogen-bonding basicity and microstructures. \u003cem\u003eGreen Chemistry, 24\u003c/em\u003e(9), 3824-3833. https://doi.org/10.1039/d2gc00374k\u003c/li\u003e\n\u003cli\u003eZhou, Z., Yao, Y., Zhang, J., Shen, L., Xu, H., Liu, J. \u0026amp; Shentu, B. (2022). Effects of poly(vinyl alcohol) (PVA) concentration on rheological behavior of TEMPO-mediated oxidized cellulose nanofiber/PVA suspensions. \u003cem\u003eCellulose, 29\u003c/em\u003e(15), 8255-8263. https://doi.org/10.1007/s10570-022-04786-1\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"cellulose","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cels","sideBox":"Learn more about [Cellulose](https://www.springer.com/journal/10570)","snPcode":"10570","submissionUrl":"https://submission.nature.com/new-submission/10570/3","title":"Cellulose","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Waste cotton, Polyvinyl alcohol, Composite fiber, Wet spinning, Regenerated cellulose","lastPublishedDoi":"10.21203/rs.3.rs-5173409/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5173409/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn order to achieve sustainable development of resources and reduce environmental pollution, it is particularly important to accelerate the use of renewable resources. Cellulose is an abundant renewable resource with biocompatible, degradable and recyclable characteristics. In order to further improve the utilization of cellulose, 1-butyl-3-methylimidazolium chloride ([Bmim]Cl)/dimethylsulfoxide (DMSO) was used to dissolve and recover cellulose from waste cotton, and regenerated cellulose (RCF) and regenerated cellulose-poly(vinyl alcohol) blended fibres (RCF/PVA) were prepared by wet spinning technology, and the pigments extracted from Pu-erh Tea were used for dyeing performance investigation of RCF/PVA. The dyeing performance of RCF/PVA was investigated. The experiments showed that, compared with RCF, the strength of RCF/PVA with 15 % PVA was improved, and the residual carbon at 700 ℃ of thermal decomposition was reduced from 21.4 % to 0.1 %. With the increase of polyvinyl alcohol content, RCF/PVA has better dyeing effect than pure cellulose regenerated fibre on the natural pigment extracted from Pu-erh tea, and the preparation of RCF/PVA provides a new way of researching new composite fibre materials.\u003c/p\u003e","manuscriptTitle":"Preparation of recycled cellulose-polyvinyl alcohol reinforced co-blended fibers based on waste cotton","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-11-13 11:18:43","doi":"10.21203/rs.3.rs-5173409/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-10-31T09:41:12+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-10-29T13:09:14+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-10-21T02:43:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"296780364510783562672078316028555137026","date":"2024-10-18T00:31:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"134740799467693665201959300172472080870","date":"2024-10-16T10:41:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"193675861434097061384182020167237656004","date":"2024-10-16T08:41:27+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-10-16T07:42:21+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-10-14T17:04:38+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-09-30T04:16:35+00:00","index":"","fulltext":""},{"type":"submitted","content":"Cellulose","date":"2024-09-29T06:58:56+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"cellulose","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cels","sideBox":"Learn more about [Cellulose](https://www.springer.com/journal/10570)","snPcode":"10570","submissionUrl":"https://submission.nature.com/new-submission/10570/3","title":"Cellulose","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"df15bb77-ca06-4554-a574-6bbb5b3f9aa9","owner":[],"postedDate":"November 13th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-01-26T16:05:18+00:00","versionOfRecord":{"articleIdentity":"rs-5173409","link":"https://doi.org/10.1007/s10570-026-06945-0","journal":{"identity":"cellulose","isVorOnly":false,"title":"Cellulose"},"publishedOn":"2026-01-23 15:58:32","publishedOnDateReadable":"January 23rd, 2026"},"versionCreatedAt":"2024-11-13 11:18:43","video":"","vorDoi":"10.1007/s10570-026-06945-0","vorDoiUrl":"https://doi.org/10.1007/s10570-026-06945-0","workflowStages":[]},"version":"v1","identity":"rs-5173409","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5173409","identity":"rs-5173409","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}