Breaking Tenacity Research Articles

Persistent Luminescent Nanoparticle-Loaded Filaments for Identification of Fabrics in the Visible and Infrared.

Persistent luminescent materials are those which can store an amount of energy locally and release it slowly in the form of light. In this work, persistent luminescent nanoparticles (PLNPs) were synthesized and incorporated into polypropylene (PP) filaments at various loading percentages. We investigated the optical properties of both the as-prepared PLNPs and the PLNP-loaded filaments, focusing on any changes resulting from the integration into the filaments. Specifically, visible and near-infrared spectroscopy were used to analyze the emission, excitation, and persistent luminescence of the PLNPs and PLNP-loaded filaments. The tensile properties of the extruded filaments were also investigated through breaking tenacity, elongation at break, Young's modulus, and secant modulus. All PLNP-loaded filaments were shown to exhibit persistent luminescence when exposed to ultraviolet light. While there were no significant changes in the elongation at break or Young's modulus for the loading percentages tested, there was a slight increase in breaking tenacity and a decrease in the secant modulus. Finally, the filaments were shown to maintain their optical properties and persistent luminescence even after abrasion testing used to simulate the normal wear and tear that fabric experiences during use. These results show that PLNPs can be successfully incorporated into filaments which can be used in fabrics and will maintain the persistent luminescent properties.

Wastepaper-Based Cuprammonium Rayon Regenerated Using Novel Gaseous-Ammoniation Injection Process.

Rayon is an extremely valuable cellulosic fiber in the global textile industry. Since cuprammonium rayon is more eco-friendly than other types of rayon fabrics, it was synthesized by regenerating α-cellulose isolated from wastepaper using a novel gaseous-ammoniation injection (GAI) process. This was achieved by preparing tetra-ammine copper hydroxide (cuoxam solution) via reacting copper sulfate and sodium hydroxide to produce copper hydroxide that was, finally, ammoniated by injecting the gas directly to the reaction vessel instead of using ammonium hydroxide applied by prior art. After that, the air-dried cellulose was chemically generated by dissolving it in a freshly prepared cuoxam solution and, subsequently, was regenerated by extruding it within a hardening bath constituted mainly from citric acid, producing the cuprammonium rayon (c. rayon). The properties of the fibrous, structural (XRD and mechanical), physical, and chemical features were investigated. It was found that the rayon was produced in a high yield (90.3%) with accepted properties. The fibrous properties of the rayon staple length, linear density, and fiber diameter were found to be 44 mm, 235 Tex, and 19.4 µm, respectively. In addition, the mechanical properties determined, namely tensile strength, elongation at break, modulus of elasticity, and breaking tenacity, were found to be 218.3 MPa, 14.3 GPa, 16.1%, and 27.53 cN/Tex, respectively. Based on this finding, and upon injecting the ammonia gas through the α-cellulose saturated and immersed in the Cu (OH)2 to complete producing the cuoxam solvent, we find that theuse of an injection rate of 120 mL/minute to obtain the highest fibers' tensile strength for the final product of the c. rayon is preferable. Utilization of higher rates will consume more amounts of the ammonia gas without gaining noticeable enhancement in the c. rayon's mechanical quality. Accordingly, the GAI invention rendered the c. rayon favorable for use in making sustainable semisynthetic floss for either insulation purposes or spun threads for woven and nonwoven textile clothing.

Characterisation of alkali-treated novel cellulosic fibres derived from Dombeya Buettneri plant as a potential reinforcement for polymer composites

ABSTRACT The present study evaluates the influence of alkali treatment using 2, 4, and 8 wt.% sodium hydroxide concentration solutions on novel cellulosic fibres manually extracted from the bark of dombeya buettneri plant (DBF). Alkali-treated fibres were characterised through physical and mechanical properties determination, Fourier transform infrared spectroscopy, X-ray diffraction, quantitative chemical analysis, thermogravimetric analysis, and scanning electron microscopy. Quantitative chemical analysis revealed a significant increment in cellulose content, reaching 67 ± 1.7% in DBF treated with 4 wt.% NaOH solution, accompanied by substantial reductions in lignin and hemicelluloses as confirmed by FTIR spectroscopy. XRD analysis showed an improved crystallinity index of 80% and crystallite size of 2.64 nm for 4 wt.% alkali-treated DBF. Additionally, 4 wt.% alkali-treated fibres yielded peak values of breaking force (40 N) and breaking tenacity (181 cN/Tex). SEM analysis confirmed enhanced surface roughness post-treatment, an indication of enhanced fibre/matrix interlocking during composite fabrication, whereas TGA analysis reported improved thermal stability post-treatment. EDX analysis confirmed that the C/O ratio is proportional to alkali solution concentration, indicating effective removal of non-cellulosic contents. In conclusion, treating DBF with 4 wt.% NaOH concentration improves their physical, mechanical, and chemical properties, suggesting their potential for polymer composite applications.

Combined effects of organic solvent and ultrasonic pretreatments on cellulose fiber extraction from hemp

Extracting pure cellulose fibers from hemp bast for potential textile industry applications requires the removal of non-cellulosic gummy materials. However, traditional degumming methods are largely limited because of the long procedure time, high energy consumption, heavy environmental pollution and insufficient efficiency. Organic solvents have been proved to be an innovative method for lignocellulose extraction. Herein, ethylene glycol solvent combined ultrasonic pretreatment was explored to degum hemp fibers without any further treatment. The purified hemp fibers were systematically characterized using analytical test techniques. Results revealed that the combined degumming could effectively remove non-cellulosic components without damaging the cellulose, and reducing the reaction temperature by 10 ℃ for reaction process. Comparing to the traditional method, the fibers by ultrasonic pretreatment-ethylene glycol process had superior average yield of 68.32 %, higher thermal stability (maximum degradation temperature reached 395 ℃), higher breaking tenacity of 6.13 cN/dtex, higher crystallinity of 78 % and the cellulose content of over 91 %. Moreover, the degumming time and chemical usage were reduced to 40 % and 51.8 %, respectively. Besides, the changes of fibers chemical structure were further investigated and verified by FTIR, EDS, and 13C NMR analysis. Featured with less chemical and energy consumption, eco-friendly and short time-consuming, this treatment has a broad application scope for hemp cellulose fiber extraction.

Robust and ultra-sensitive self-powered fire warning sensor based on polyimide thermoelectric fibers for temperature sensing and intelligent fire safety monitoring

Fire warning sensors is crucial to effectively prevent fire accidents in a variety of modes and meet the needs of the connected age. Nevertheless, there is still a formidable challenge in fabricating self-powered fire warning sensors that are flexible and can be integrated in combustible materials. In this work, flexible high-fireproof polyimide (PI)/hydroxyapatite (HAP)/Ag2Se composite aerogel fiber (PHA-AF) was fabricated by specific wet spinning technology. The extraordinary thermoelectric effect of Ag2Se enabled PHA-AF to achieve precise temperature sensing over a wide temperature range of 100 °C–500 °C. Simultaneously, the PHA-AF-based fire alarm sensor could trigger a fire alarm system in 1.9 s and respond continuously for 14 s under flame attack, while generating output voltage of up to 5.9 mV in self-powered mode. Notably, PI as a flame-retardant material could be formed the 3D networks with HAP, as well as the skeleton support effect provided by Ag2Se nanorods enabled PHA-AF based fire alarm sensors with superior breaking tenacity (2.9 MPa), strong heat stability (maximum weight loss rate at 550 °C) and flame retardancy (LOI = 35.8 %), further highlighting its authenticity, repeatability, and reliability in fire. This work offers potential for the preparation of fiber-based self-powered early fire alarm sensors for long-term continuous using in harsh fire environment.

Investigation and application of different extraction techniques for the production of finer bamboo fibres

Bamboos are an important source of fibres. Natural bamboo fibres possess have characteristics that make them of potential use in textiles. However, they have not received the attention they deserve due to the difficulty of extracting finer fibres. Full utilization of the potential of bamboo requires the extraction of the fibres using advanced techniques. In this study, three different extraction methods were developed, utilizing a newly created composite enzyme and alkalis in combination to extract finer natural bamboo fibres. The new enzyme was applied in both a solid form and a liquid state. Mechanical processes were also employed in preparing the bamboo culms and extracting the fibres. Three commonly grown bamboo species, Bambusa emeiensis (Neosinocalamus affinis), Phyllostachys edulis (Phyllostachys heterocycla), and Phyllostachys reticulata (Phyllostachys bambusoides), were used in the study to extract natural bamboo fibres. The bamboo samples were treated with 3–6% alkali and 24–36% composite enzyme, based on their weight. The composite enzyme was a recently developed enzyme that was used in both a liquid form and a solid form without the need for water as a solvent (non-aqueous treatment). The physical properties such as moisture content, length and fineness, and mechanical (tensile) properties such as breaking tenacity, breaking load and breaking extension of the resulting fibres were assessed with their minimum, maximum and average values. Structural analyses were performed using infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal analyzer (TGA) and scanning electron microscopy (SEM). The yield percentages of bamboo fibres were also determined. The bamboo fibres had a moisture content of 7.32–7.71%, an average length of 5.48–6.01 cm, a linear density of 9.71–11.43 tex, a breaking load of 138.96–147.67 cN, a breaking tenacity of 12.16–15.21 cN/tex, and a breaking elongation of 2.60–2.75%. SEM, TGA and FTIR tests indicated that the fibres were not single cellulosic fibres but rather fibre bundles in which single fibres were bonded by lignin and hemicellulose. The TGA results showed that the fibres were sufficiently thermally stable to withstand high temperature textile processes. The XRD results indicated the improvement of the crystallinity of the natural bamboo fibres owing to the partial removal of the non-crystalline lignin and other components. The measured properties of the fibres showed standard deviation values of 0.36–2.52, indicating a high level of uniformity within each sample. The experimental results demonstrated that the fibres obtained in this study have the potential to be used in textiles. The fibre yield percentages (approximately 52.7–55.2%) confirmed that all three bamboo species have the potential to provide usable fibres.

Ultra‐high molecular weight polyethylene micro‐ribbon fibers gel spun using orange terpenes

AbstractToxic, hazardous petrochemical solvents are commonly used for industrial‐scale ultra‐high molecular weight polyethylene (UHMWPE) fiber production, but orange terpenes, a byproduct of orange fruit production, present a bio‐derived, sustainable alternative. In this work, fine UHMWPE fibers were spun using orange terpenes as the spin solvent, hot‐drawn at a draw ratio of 5:1, investigated for their morphology, microstructure, and thermal and mechanical properties. The resulting fibers exhibited a flat, micro‐ribbon cross‐section, which is highly desirable for achieving high fiber volume fractions in UHMWPE‐fiber reinforced composites. After drawing, the fibers possessed 4× greater breaking tenacity than any previously published studies on UHMWPE fibers spun using orange terpenes with a tenacity of 8.6 cN/dtex and tensile modulus of 229.2 cN/dtex. Microstructural analysis via differential scanning calorimetry and X‐ray diffraction revealed that the hot drawing process significantly increased molecular orientation, but crystallinity decreased due to crystallite melting during drawing. Therefore, the mechanical properties of these fibers may be significantly improved with optimization of the fiber drawing process. This work establishes the strong potential of orange terpenes as an environmentally‐friendly alternative solvent for UHMWPE gel spinning and sets a foundation for future parametric optimization of the spinning and drawing of these fibers.Highlights Micro‐ribbon ultra‐high molecular weight polyethylene fibers were prepared using bio‐solvent orange terpenes. Flat profile enables tight packing, aspect ratio maintained after drawing. Drawn fibers were 4× stronger than any previous work with orange terpenes. Near‐melt drawing reduced crystallinity, improved molecular alignment.

Biosoftening of banana pseudostem fiber using cellulase and pectinase enzyme isolated from Aspergillus niger for textile industry

BackgroundNowadays, farmers are facing a lot of problems for the disposal of banana pseudostem waste after the harvesting of banana. Banana pseudostem is a rich source of fiber, which is an alternative source of other natural and synthetic fibers. The banana fibers are biodegradable, and they are expected to be in great demand in the international market. For the textile industry, fibers were extracted using chemical and mechanical methods, but it leads to damage and affects the quality of fibers. So, this study mainly focused on biosoftening of banana pseudostem fiber using crude enzyme produced from Aspergillus niger which is one of the most predominant fungus which can synthesize industrially applicable enzymes and which can soften the surface of banana pseudostem fiber. Through this, biosoftened banana pseudostem fiber can be produced, and the disposal problem of banana pseudostem can be rectified in an eco-friendly manner. ResultThe present study was undertaken for the biosoftening of banana pseudostem fiber using crude enzymes isolated from fungal strain. The fungal isolates were subjected to enzyme screening such as cellulase, pectinase, chitinase, peroxidase, and polygalacturonase. The maximum production of enzyme was observed in F2 strain, and it was subjected to crude enzyme production and purification using dialysis and column chromatography. The collected best enzyme fractions were selected for the biosoftening of banana pseudostem fiber. The banana pseudostem fiber was treated with crude enzymes at the time duration of 2, 4, 24, and 48 h. After the treatment, the treated and untreated fibers were evaluated for the mechanical properties and chemical constituent’s analysis. The results revealed that the chemical contents were high during 2- and 4-h-treated fibers. After that, chemical constituents were reduced due to the removal of debris by the action of enzymes. The mechanical properties such as breaking load, breaking extension, tenacity, and diameter of fiber were best in the fibers treated for 2 and 4 h. After 4 h due to the removal of chemical constituents the breaking load and tenacity, diameter will be reduced. SEM results proved that the fiber treated at 4th h showed smooth and softened fiber. ConclusionThis study proved that the crude enzymes isolated from the Aspergillus niger can be effectively soften and increase the quality of banana pseudostem fiber.

Regenerated bacterial cellulose fibres

The global shortage of cotton for textile production, forces the exploitation of forests´ lignocellulosic biomass to produce man-made cellulosic fibres (MMCF). This has a considerable environmental impact, pressing the textile industry to search for new sustainable materials and to the development of sustainable recycling processes. Bacterial cellulose (BC), an exopolysaccharide produced by fermentation, could represent such an alternative. In particular, we tested the possibility of improving the mechanical properties of cellulose filaments with a low degree of polymerization (DP) by combining them with high DP from BC, so far exploited to little extent in the textile field.In this work, BC with different degrees of polymerization (DPcuaxam) (BCneat: 927; BCdep:634 and BCblend: 814) were dissolved in N-methylmorpholine-N-oxide (NMMO) and their spinnability was studied. The rheological behaviour of the dopes was assessed and all were found to be spinnable, at suitable concentrations (BCneat:9.0 %; BCdep:12.2 %; BCblend:10.5 %). A continuous spinning was obtained and the resulting filaments offered similar mechanical performance to those of Lyocell. Further, the blending of BC pulps with different DPs (BCblend, obtained by combining BCneat and BCdep) allowed the production of fibres with higher stiffness (breaking tenacity 56.4 CN.tex−1) and lower elongation (8.29 %), as compared to samples with more homogeneous size distribution (neat BC and depolymerized BC).

Characterization of Banana Fibers Extracted with Pectinase from Staphylococcus sciuri

Various methods of isolating cellulosic fibers from banana pseudo-stems including mechanical extraction, steam release, steam release combined with chemical treatment, and an enzymatic method with pectinase from Staphylococcus sciuri, were performed. The fibers were produced by all the methods and characterized. In this work, we report on the breaking tenacity, breaking strength, fiber length, diameter, toughness, and linear density of enzyme-retted fiber. Banana cellulose fiber isolated by the enzymatic retting procedure was comparable in physical properties to cotton fiber and was also shown by FTIR analysis to contain cellulose, lignin, and hemicellulose. The banana cellulose fibers had the following characteristics: linear density of 161.81 denier, breaking tenacity of 38.50 g/tex, elongation of 4.03%, fiber diameter of 127.02 m, and fiber length of 191.68 mm.

A Facile Method to Manufacture the Sesamum Indicum Fibers by Glycolic Acid Assisted with Microwave

ABSTRACT The Sesamum indicum bast contains more hemicellulose, lignin, and flaky parenchymal cells than the commonly used ramie bast, which are rigid for the degumming process. We explored a facile and greener method by using glycolic acid microwave-assisted treatment combined with alkaline treatment to effectively and low-cost prepare the high-quality Sesamum indicum single fibers. The chemical and physical properties of fibers were analyzed by chemical composition analysis, SEM, FTIR, XRD, TG, and GPC analysis. The residual gum content was decreased from 34.4% to 4.2%, resulting in a cleaner micro-surface of the Sesamum indicum fibers with increased cellulose crystallinity (75.2%–82.5%) and thermal stability (357°C–365°C). The fiber fineness (2.5 dtex) and breaking tenacity (4.9 cN/dtex) of the fibers produced by the novel treatment method exhibited the same level compared with the traditional two-step alkaline fibers. Besides, both the consumption of water and the chemicals was decreased compared with traditional degumming. This work provided a novel green and facile degumming method for processing the natural bast fibers.

Valorization of Corn Husk Waste for Textile Applications

ABSTRACT Agriculture biomass is a widely known renewable source that has a high possibility of recycling. The present investigation deals with the extraction, pre-treatment, dyeing, and characterization of natural fiber obtained from agricultural residues of corn husk. Water retted corn husk fibers were subjected to two steps of scouring and bleaching with hydrogen peroxide. The process effectively reduced non-cellulosic impurities, increased cellulose content to almost 79%, enhanced water absorption (431.5%), and increased fiber whiteness (54) with minimal impact on breaking tenacity (17.17 CN/tex). Natural dyeing was performed by using dye extracted from Sappan wood, and it was observed that fiber dyed without mordant exhibits a good color strength (K/S) of 13.21. Optimum dyeing conditions were determined by the response surface methodology, where K/S was kept as the main response. Modern spectroscopic characterization techniques were used for confirmatory analysis. The optimized recipe for natural dyeing is a 20% liquid dye concentration at 70°C for 1 hour, which achieved a K/S of 10.2–10.5 with adequate wash and light fastness properties in the range of 3–4 and 7–8, respectively. The current study will pave the way for the efficient textile application of this abundant but unnecessarily wasted biomass.

Comparison of tensile properties of needle punched nonwoven fabric produced by bi-directional and unidirectional barb needles employing response surface methodology

In production of needle punched nonwoven fabrics, direction of needle barbs is towards the tip of the needle. When the needle penetrates into the fabric, the barbs carry some fibres into the fabric and when it returns the barbs are empty. This means that the needle works when it penetrates into the fabric and doesn’t work when it returns. Using a bi-directional barb needle in the needle-punch process was proposed as an idea with the theory that the needle also works when returning (leaving the fabric). In this study, the test specimens were prepared by two type of needles in an industrial needle machine. Fibre displacement at fabric cross-section was examined by optic and scanning electron microscopy for two types of needles. An experiment with 190 samples was produced using the response surface methodology and optimal design with two quantitative factors, including the number of strokes per minute and needle penetration depth, and one qualitative factor containing needle types. In addition, six responses were measured and reported in the machine direction and cross direction, including breaking load, extension, and tenacity. According to the findings, the tensile characteristics of non-woven (NW) fabrics generated produced by bi-directional barbed needles were higher than those produced by unidirectional barbed needles.

Anthraquinone-assisted deep eutectic solvent degumming of ramie fibers: Evaluation of fiber properties and degumming performance

Deep eutectic solvent (DES) is proved to be versatile for ramie fiber isolation due to its high degumming efficiency and feasible recycling process. However, ramie cellulose is easily to be chemically degraded during the intense reaction if the treatment conditions cannot be properly controlled, affecting the mechanical properties of ramie fibers. In this paper, anthraquinone (AQ), serving as effective cellulose protection agent, was applied in the process of DES degumming to enhance the properties of treated fibers. Under the addition of 0.2 g/L AQ, there was an increase of 3.2% in the degree of polymerization and 5.56% in the crystallinity. Besides, the breaking tenacity, breaking elongation, and work of rupture of degummed fibers increased by 8.44%, 11.94%, and 33.33%, respectively. The chemical structure and thermal properties were also analyzed and compared between degummed fibers with or without cellulose protection agent. It is found that a small amount of AQ could improve the degradation temperature of fibers, accelerate the removal of lignin, and protect carbohydrates from excessive degradation. Considering these significant advantages, intrinsic greenness of DES, as well as the auxiliary effect and inexpensiveness of AQ, this new degumming method holds enormous potential for natural fiber extraction.

Assessment of Changes in Corn Husk Fibres after Acid Treatment

Sustainability is desirable in any activity, including farming. Adding value to agricultural wastes such as stover (waste from corn cultivation) would provide financial benefits to farmers while reducing the environmental load of disposal. The literature identifies stover as being a raw material for bio-ethanol and a reinforcement for composites. Fibre from corn husks is generally extracted using an alkali digestion method followed optionally by enzymatic degradation. In this study, acid treatment was investigated for its feasibility to improve the desirable characteristics of alkali extracted corn husk fibres. The results revealed that increasing the acid concentration decreased fibre properties such as average fibre length, linear density and elongation at break. However, breaking tenacity achieved a maximum value, on treatment with 7.5 g/l sulfuric acid, before decreasing. These properties indicate the treatment’s adequacy for use in textile products. Acid treatment did not significantly alter thermo-gravimetric analysis values, indicating that the fibre could withstand wet processing conditions.

Effect of Ailanthus species and seasons on yarn parameters of eri silk

Present research entails an in-depth analysis on the effect of two secondary host plants of eri silkworm viz., borpat (Ailanthus grandis Prain) and borkesseru (Ailanthus excels Roxb.) and seasons on yarn parameters of eri silk as quality of silk depends on food quality and rearing season. Seasons had significant effect on all the yarn parameters viz., yarn size, breaking load, tenacity and elongation except twist per inch. Significantly the highest yarn size (10.26s) was observed in autumn season which was at par with the spring season. But the maximum breaking load (0.67 kg) and tenacity (1.40 g/denier) were recorded in spring season and elongation (26.54%) in early summer season. Regardless of the seasons, significantly the higher breaking load (0.64 kg) and tenacity (1.51 g/denier) were recorded on the borkesseru leaves. The interaction effect of seasons and two host plants on eri silk yarn was found to be non-significant. Diversiform effect of both the seasons and the host plants pertaining to yarn characters were witnessed. It can be ensured that all the seasons and host plants are relevant with slight alteration in the yarn quality.

Modification of the Mechanical and Structural Properties of Sisal Fiber for Textile Applications

ABSTRACT Sisal fibers are reported to have outstanding textile properties including high strength, absorbency, good dye uptake, exceptional durability and abundant availability suggesting their potential in clothing applications. However, sisal fibers have not received the attention they deserve owing to their coarseness and stiffness that limit their application to non-clothing products. This study investigated potential chemical methods to modify the surface structure of sisal fibers, thereby allowing their application in clothing production. The effect of the treatment on sisal fibers was established by their mechanical properties, moisture content (M C) and regain (M R), and structural properties. The treatment produced fibers with 28.6 Tex fineness, an average length of 68.5 cm, a breaking tenacity of 385.6 mN/tex and 3.9% elongation. Furthermore, the investigation revealed that alkali treated sisal fiber had M C and M R of 10.53% and 11.77%, respectively. These parameters were comparable to most cellulosic fibers including cotton, flax and jute. The thermal stability of sisal fibers was observed to increase upon modification as studied by using a Thermogravimetric Analyzer (TGA), whereas the Infrared spectra of both unmodified and modified fibers revealed the effect of chemical modification. These results suggest a possibility of developing sisal fibers for clothing applications.

Bleaching flax roving with poly(acrylic acid) magnesium salt as oxygen bleaching stabilizer for hydrogen peroxide

Alkali-oxygen one-bath scouring and bleaching process of the flax roving was studied by using a new type of synthesized non-silicon oxygen bleaching stabilizer Poly(acrylic acid) magnesium instead of sodium silicate. Based on the analysis of the effects of single factors such as sodium hydroxide concentration, hydrogen peroxide concentration, temperature, time and the amount of the synthesized non-silicon oxygen bleaching stabilizer poly(acrylic acid) magnesium salt on the performance of the bleached flax roving, including the whiteness, the breaking tenacity, the capillary effect and the weight loss ratio. The optimal process for the application of the stabilizer was determined by orthogonal test, namely, hydrogen peroxide concentration 8.5 g/L, sodium hydroxide concentration 5 g/L, sodium bisulfite 3 g/L, sodium carbonate 3 g/L, the synthesized non-silicon oxygen bleaching stabilizer poly(acrylic acid) magnesium 5.5 g/L, scoured and bleached at 90 °C for 60 min, and the bath ratio was 25:1. Compared with the traditional oxygen bleaching stabilizer sodium silicate, it not only has good ability to inhibit the rapid decomposition of hydrogen peroxide, but also has the advantages of higher whiteness, higher capillary effect, good feel and breaking tenacity, and can effectively solve the "silicon scale" problem and improve the quality of flax products. A novel non-silicon oxygen bleaching stabilizer poly(acrylic acid) magnesium was synthesized and successfully applied to alkali-oxygen one-bath scouring and bleaching process of the flax roving, effectively solving the "silicon scale" problem caused by conventional sodium silicate as stabilizer.

Research on Chemically Deuterated Cellulose Macroperformance and Fast Identification.

Chemically deuterated cellulose fiber was expected to provide novel applications due to its spectral, biological, and kinetic isotope effect. In this research, the performance of the chemically deuterated cotton fibers, including their mechanical property, enzymatic degradation performance, effect on bacterial treatment, and fast identification (near-infrared modeling) was investigated. The breaking tenacity of the deuterated cotton fibers was slightly lower, which might be attributed to the structural damage during the chemical deuteration. The glucose yield by enzymatic hydrolysis was less than that of the protonic cotton fibers, implying the deuterated fibers are less sensitive to enzymatic degradation. Furthermore, the deuterated fibers could promote the growth of bacteria such as Escherichia. coli, which was associated with the released low-level deuterium content. At last, the near-infrared technique combined with partial least squares regression successfully achieved a fast identification of the protiated and deuterated cotton fibers, which significantly promoted the potential application of deuterated cellulose as anticounterfeiting materials (e.g., special paper).

Eco-friendly Process to Degum Flax Roving with Deep Eutectic Solvent and Microbial Treatment

ABSTRACT Flax is an economically important fiber crop, however, it requires degumming to yield usable fibers. The degumming process of flax roving is a key step in flax processing and production. In this study, deep eutectic solvent (DES; choline chloride–urea) pretreatment was combined with microbial treatment to develop an ecofriendly and effective degumming method for flax roving. The optimal conditions for DES pretreatment (100°C for 120 min with 90% DES) were obtained through orthogonal tests. DES combine microbial treatment could effectively remove gum from the flax fibers. The flax roving fibers were characterized by chemical analyses, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffractometry, and thermogravimetric analysis. Compared with fibers treated with microbes alone, flax roving fibers subjected to DES combine microbial treatment showed better breaking tenacity (16.77 cN/tex) and average pectin, hemicellulose, and lignin removal rates of approximately 86.4%, 26.7%, and 55.1%, respectively. NMR revealed that the composition of DES was not damaged during pretreatment, which means the bulk solution could be reused. This research showed that DES combine microbial treatment is feasible and effective method for flax roving degumming.