Chemical Fiber Research Articles

Characterization of cocoa (Theobroma cacao L.) wood branches as a potential resource for paper production

For sustainable use of lignocellulosic resources, pruned tree branches of cocoa, one of the major evergreen tropical tree crops with significant economic importance worldwide, were investigated as a potential source of kraft pulp. This study determined the chemical composition, fiber dimensions, kraft pulp, and paper properties of the cocoa tree (Theobroma cacao L.) branches compared to the deciduous trees traditionally used in the paper industry. A handsheet of cocoa pulp showed promising results with narrow fiber length distribution, high paper density, and high mechanical strength. The yield of kraft pulp made from cocoa branches wood was lower. The tensile and burst indices of cocoa pulp handsheet were 2 and 2.5 times higher than that of hardwood traditionally used in the paper industry. These results suggest a potential use of cocoa (Theobroma cacao L.) tree branch wood for pulp production using the kraft process.

Bacterial cellulose production through the valorization of waste apple pulp and stale bread

AbstractIn this work, stale bread and waste apple pulp were used as feedstocks for the production of bacterial cellulose (BC). A glucose-rich solution was prepared from stale bread by dilute acid hydrolysis, while an extract comprising fructose and glucose was obtained from the waste apple pulp, which was used for cultivating Komagataeibacter xylinus DSM 2004, either as sole feedstocks or supplemented with Hestrin-Schramm medium. Supplementation significantly improved BC production: 3.38 ± 0.09 g/L for waste apple pulp extract and 2.07 ± 0.22 g/L for stale bread hydrolysate. There was no significant impact on BC chemical structure or fiber diameter, but the biopolymer produced from waste apple pulp extract had slightly higher crystallinity (CI = 59–69%) and lower thermal degradation temperature (Tdeg = 341–350 ℃) than that of the stale bread hydrolysate (CI = 55%; Tdeg = 316–320 ℃). Moreover, supplementation of the waste apple pulp extract led to the preparation of thicker membranes, with higher Young’s modulus, tension, and deformation at break but lower water uptake capacity and lower permeability to O2 and CO2. These results show that waste apple pulp and stale bread are suitable feedstocks for BC production and the cultivation conditions can be adjusted for tailoring the biopolymer’s mechanical and barrier properties to suit different applications.

Nutritional Value Evaluation of New Pea Genotypes (Pisum sativum L.) Based on Their Chemical, Amino Acids and Dietary Fiber Composition.

This research concerned the assessment of the utility value of new pea breeding materials intended for registration in the European Union. The research material consisted of sixteen breeding lines and four reference pea varieties. The evaluation was carried out based on the chemical composition of seeds and its variability within the studied genotypes. The contents of protein, starch, lipids, ash and dietary fiber (DF) were determined. The nutritional value of the protein was assessed in vitro using the value of the limiting amino acid index chemical score (CS) and the integrated essential amino acid index (EAAI). The analyzed pea genotypes were characterized by significant diversity in terms of the content of the tested components. The obtained results combined with the PCA analysis were used to select pea genotypes of the highest quality, having the potential as a raw material for the production of food with health-promoting properties. The effect of the conducted research was the identification of three pea genotypes with the greatest potential in terms of protein content and dietary fiber complex.

Fluorine containing diamond-like carbon coatings

Fluorine containing diamond-like carbon (DLC) coatings were obtained by CVD deposition using the destruction of gaseous hydrocarbons by a high-energy ion source with an anode layer. The chemical composition, structure, surface energy, mechano-tribological characteristics of the synthesized thin-film material were studied. It has been shown that the fluorine content in the deposited coatings reaches 31 at.%. It has been established that the presence of fluorine in the DLC coating promotes the formation of nanodispersed graphite-like structures. Fluorine containing coatings with a high content of sp2 hybridized carbon atoms and graphite fragments show a decrease in hardness. Such coatings have a very low coefficient of friction at the level of 0.03–0.07 due to the low surface energy, which can be reduced by 1.5 times compared to pure DLC. It has been established that different fluorine contents in thin-film diamond-like carbon material have different effects on the interaction of the DLC coating with polar/non-polar dielectrics. The research results can be used for the technology of producing solid lubricants in friction units of machines and mechanisms, and are also of interest for medicine, the food industry, the production of plastics, and chemical fibers as chemically inert and corrosion-resistant coatings.

A polyhedron-based metal-organic framework with electronegative donor sites for efficient C2H6/C2H4 separation

Ethylene is an important chemical raw material which is widely used in the production of chemical fibers, plastics, rubber, coatings, as well as medicines, and its separation from the gas mixtures of C2H6/C2H4 is of great importance but a challenging task due to their similar physical properties and molecular dimensions. Herein, we report the C2H6 and C2H4 sorption studies on a robust anionic metal-organic framework (MOF) {(NH2Me2)[Co3(μ3OH)(TPT)(TZB)3](H2O)6(DMA)6}n (Co-MOF) formed by connection of Co3(OH) clusters by two N-rich organic ligands 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT) and 4-(1H-Tetrazol-5-yl)benzoic acid (H2TZB). The prepared Co-MOF features a polyhedron stacking network structure composed of trigonal bipyramidal cages and octahedral cage which both contribute to a high C2H6 uptake capacity of 6.48 mmol/g and a decent C2H6/C2H4 selectivity of 1.54 at 298 K and 1 bar. Grand Canonical Monte Carlo (GCMC) simulation results agree well with the experimental tendency, both in the adsorption isotherms and sorption heats, which demonstrated that the suitable pore surfaces with electronegative donor sites generated multiple CH ⋅⋅⋅O/N and CH ⋅⋅⋅π interactions between the framework and C2H6, resulting in a stronger interaction between the MOF skeleton and C2H6 molecule than C2H4 as reflected by the dispersion-corrected density functional theory (DFT) calculation.

DIDACTIC AND METHODOLOGICAL BASES FOR ENSURING THE STUDY OF CHEMISTRY BY FUTURE SPECIALISTS OF TECHNOLOGICAL AND VOCATIONAL EDUCATION

The article actualizes the research task of substantiating the didactic (content of the leading topics) and methodological (topics and objectives of laboratory work) foundations for ensuring general and professionally oriented competencies in the study of chemistry by future technology teachers and vocational education specialists. It is proposed to include the following topics in the content of training of higher education applicants majoring in 014.10 Secondary Education (Technology): basic concepts and laws of chemistry, periodic law and the D. Mendelieev’s periodic table of chemical elements; main classes of inorganic compounds; hydrocarbons; oxygen-containing organic compounds; non-trogen-containing organic compounds; general properties of high molecular weight compounds; chemical fibers; plastic masses. This block of the discipline includes laboratory work developed by the article author in accordance with the content of each topic. The article concludes the importance of chemical disciplines in the implementation of the educational profiles «Woodworking», «Agricultural Production», «Cooking», «Construction», «Energy», «Design and Modeling of Clothes», «Light Industry», «Design Basics», «Metalworking», etc. in high school in Ukraine.

The development of polymers and fibers: an interview with Stephen Cheng.

Polymer and fiber science has evolved significantly since the 1920s, with polymers becoming integral to both industry and daily life. China's fiber research, initiated in the 1950s, has made substantial societal and technological contributions, particularly in chemical fibers. How will future advancements in polymers and fibers address ongoing challenges and drive further innovation? NSR spoke to Prof. Stephen Cheng, a member of the National Academy of Engineering (U.S.) and former Dean of the College of Polymer Science and Polymer Engineering at the University of Akron. He is currently Dean and Honorable Professor at South China University of Technology. His research interests center on the condensed states in polymers, liquid crystals, surfactants and hybrid materials, focusing on the interactions, responses, dynamics and structures of materials at varying lengths, energy and timescales, in which the material itself embodies the technology.

Self-adhesive fiberboards fabricated from waste bamboo powder through biological pretreatment

Using renewable and sustainable agricultural and forestry wastes to produce bio-based materials is an effective approach for significantly reducing the environmental pollution caused by petroleum-based materials such as plastics and chemical fibers. This research aims to develop a cleaning process for large-scale production of high-performance green bio-based materials without the use of any chemical binders. The mechanical properties of self-adhesive fiberboards are improved through pretreatment with white rot fungi. By pretreating bamboo powder with biological factors like sugars and laccase produced by white rot fungi under high temperature and pressure, lignin-active molecules are formed on the surface. These active molecules can reconstruct chemical bonds between multi-fiber materials, thereby exhibiting biological adhesion. The reconfiguration of lignin molecules on the material's surface also helps prevent rapid water penetration. After biological pretreatment, the surface of bamboo powder forms a concave-convex structure, effectively increasing the area of biological adhesion during hot-pressing conditions. Compared to regular bamboo powder control samples, bio-pretreated fiberboards showed an increase in modulus of rupture (MOR) by 83.33 % and modulus of elasticity (MOE) by 100.79 %. In contrast to traditional fossil-based adhesive synthetic materials, the findings of this study circumvent the emission of harmful volatiles from chemical adhesives while effectively substituting petroleum-based synthetic materials that necessitate diverse chemical additives, which are in alignment with the principles of environmental protection and sustainable development.

Surface physics and chemistry of carbon fibers enhance dissimilar sheet joining of carbon fiber-reinforced plastic by copper electrodeposition

Carbon fiber-reinforced plastic (CFRP) sheets were dissimilarly edge-joined with anodized A6061 Al alloy sheets by copper electrodeposition. A high bonding strength of 137 MPa was attained following a series of pretreatments including etching in KMnO4 + NaOH hot aqueous solution, anodization at 2 V vs. SUS316 cathode in 1 mol L˗1 H2SO4, and sulfonation in hot concentrated H2SO4. The anodization physically cleaned the carbon fiber (CF) surface in CFRP. The chemical surface properties of the CFs were modified by the anodization, introducing crystallographic defects and CO groups. This physical and chemical modification of CFs in CFRP resulted in good adhesion of the electrodeposited copper.

Chemical treatment, fibre length, and fibre loading affecting the mechanical and morphological characteristics of flax fibre/polylactic acid (PLA) green composites developed by injection moulding

AbstractThis paper presents the parametric investigation and optimization of various chemical treatment parameters that affect the mechanical performance of the green composite. The injection moulding method was used to produce the green composites using flax fibre (FF) and polylactic acid (PLA). The chemical parameters chosen to investigate their effects are chemical type (sodium hydroxide, sodium carbonate, and potassium hydroxide), chemical concentrations (1 %, 2 %, and 3 % (w/v)), and duration for fibre treatment (2 h, 4 h, and 6 h). The mechanical performance of the green composites was assessed by evaluating the various properties namely strength, modulus, and elongation under tensile, share, flexural, and compression loading conditions. The morphological study was also performed to examine the failure behavior of the composite after mechanical testing. The effect of fibre length (2 mm, 3 mm, 4 mm, 5 mm, and 6 mm) and fibre loading (10 wt.%, 20 wt.%, and 30 wt.%) on the performance of the flax fibre (FF)/polylactic acid (PLA) composite was also investigated. The fibre dispersion, fibre orientation, and fibre length retention were investigated to assess the characteristics of fibre during injection moulding of the developed flax fibre (FF)/polylactic acid (PLA) composite.

Bifunctional naringenin-laden gelatin methacryloyl scaffolds with osteogenic and anti-inflammatory properties

ObjectiveTo fabricate and characterize an innovative gelatin methacryloyl/GelMA electrospun scaffold containing the citrus flavonoid naringenin/NA with osteogenic and anti-inflammatory properties. MethodsGelMA scaffolds (15 % w/v) containing 0/Control, 5, 10, or 20 % of NA w/w were obtained via electrospinning. The chemical composition, fiber morphology/diameter, swelling/degradation profile, and NA release were investigated. Cytotoxicity, cell proliferation, adhesion and spreading, total protein/TP production, alkaline phosphatase/ALP activity, osteogenic genes expression (OCN, OPN, RUNX2), and mineralized nodules deposition/MND with human alveolar bone-derived mesenchymal stem cells (aBMSCs) seeded on the scaffolds were assessed. Moreover, aBMSCs seeded on the scaffolds and stimulated with tumor necrosis factor-alpha/TNF-α were submitted to collagen, nitric oxide/NO, interleukin/IL-1α, and IL-6 production assessment. Data were analyzed using ANOVA and t-student/post-hoc tests (α = 5 %). ResultsNA-laden scaffolds presented increased fiber diameter, lower swelling capacity, and faster degradation profile over 28 days (p < 0.05). NA release was detected over time. Cell adhesion and spreading, and TP production were similar between GelMA and GelMA+NA5 % scaffolds, while cell proliferation, ALP activity, OCN/OPN/RUNX2 gene expression, and MND were higher for GelMA+NA5 % scaffolds (p < 0.05). Cells seeded on control scaffolds and TNF-α-stimulated presented higher levels of NO, IL-1α/IL-6, and lower levels of collagen (p < 0.05). In contrast, cells seeded on GelMA+NA5 % scaffolds showed downregulation of inflammatory markers and higher collagen synthesis (p < 0.05). SignificanceGelMA+NA5 % scaffold was cytocompatible, stimulated aBMSCs proliferation and differentiation, and downregulated inflammatory mediators’ synthesis, suggesting its therapeutic effect as a multi-target bifunctional scaffold with osteogenic and anti-inflammatory properties for bone tissue engineering.

Ultra-fast catalytic oxidation of persulfate by waste fiber carbon with lattice distortion

Every year, a staggering 920,000 tons of chemical fiber textiles are discarded globally, presenting a pressing global challenge of how to extract their high-value utility. This research is dedicated to recovering carbon from waste chemical fiber textiles for catalytic oxidation and degradation of pharmaceutical intermediates in wastewater. Through the interaction of sulfonation and nitrogen doping, a synthetic fiber known as nitrogen-sulfonated doped carbon (SNBC) was skillfully synthesized, resulting in lattice distortion that effectively regulates the p-band center of the catalyst. The result was a significant increase in the interfacial electron transfer rate, which increased the surface electron transfer rate and catalytic removal rate of bisphenol AF by more than 6 times, while greatly reducing the number of oxidants required. This study provides an efficient method for the resource utilization of waste synthetic fiber textiles, which has the characteristics of low energy consumption and high economic benefit.

Enzyme activity test paper with high wet strength and anion adsorption properties fabricated from whole cationized softwood chemical fiber

Paper-based test film material is widely used in a variety of test instruments for different applications. The enzyme activity test paper sheet is one of the most popularly used test papers. Here we present a novel fabrication of paper-based enzyme activity test paper without cationic resin added in. The chemical pulping fibers were first beaten to different degrees (from 14.6 to 41.5°SR) with a PFI beater. After that, the fibers were modified with a cationic agent (3-chloro-2-hydroxypropyl trimethyl ammonium chloride) under the system of alkali and water solution. Finally, the test papers were made with the modified fiber by a regular paper former in lab. The results showed that beating is beneficial for the improvement of the cationization reaction which is indicated by the Zeta potential, FTIR and EDS. The main mechanisms involved are the destruction of crystalline zone, increase of free hydroxyl group and defibrillation. This hypothesis was supported by the SEM, XRD and fiber analyzer. Beating under the optimized condition, the wet strength and liquid absorbability of test paper can meet the application requirement, and the test results of enzyme activity are quite close to those of commercial test papers.

Evaluation of physicochemical properties of Rohu fish noodles

Functional noodles are considered nutritious and healthy staple food products. This study aimed to develop value-added rohu fish noodles (Labeo rohita) and evaluate their physicochemical properties. Six noodle samples were prepared following several formulations. After a 2-day drying process, the noodles were stored in air-resistant plastic bags. The formulated noodles were investigated based on their physical (water absorption capacity, cooking loss, and volume increase) and chemical (moisture, ash, protein, fat, and fiber) properties. Statistical analysis revealed that the inclusion of rohu fish mince significantly increased moisture and protein content (p<0.01), while carbohydrate, energy, water absorption capacity, cooking loss, and volume decreased significantly (p<0.01). Noodles with the highest fish mince content (30%) demonstrated a higher amount of moisture (13.07%), ash (6.7%), fat (1.87%), protein (30.08%), sodium (0.64 mg), and calcium (0.26 mg), accompanied by reduced carbohydrate (48.3%) and energy (330.31 kcal). This formulation also exhibited lower water absorption capacity, cooking loss, and volume. Notably, no significant differences (p>0.05) were found in ash, fiber, fat, and mineral content among the various fish noodle samples. This study concludes that the incorporation of rohu fish mince can enhance the nutritional properties of traditional noodles.

The Soret effect in laser chemical vapor-deposited carbon fibers

The Soret effect in laser chemical vapor-deposited carbon fibers

AI-Driven Optimization of PCL/PEG Electrospun Scaffolds for Enhanced In Vivo Wound Healing.

Here, an artificial intelligence (AI)-based approach was employed to optimize the production of electrospun scaffolds for in vivo wound healing applications. By combining polycaprolactone (PCL) and poly(ethylene glycol) (PEG) in various concentration ratios, dissolved in chloroform (CHCl3) and dimethylformamide (DMF), 125 different polymer combinations were created. From these polymer combinations, electrospun nanofiber meshes were produced and characterized structurally and mechanically via microscopic techniques, including chemical composition and fiber diameter determination. Subsequently, these data were used to train a neural network, creating an AI model to predict the optimal scaffold production solution. Guided by the predictions and experimental outcomes of the AI model, the most promising scaffold for further in vitro analyses was identified. Moreover, we enriched this selected polymer combination by incorporating antibiotics, aiming to develop electrospun nanofiber scaffolds tailored for in vivo wound healing applications. Our study underscores three noteworthy conclusions: (i) the application of AI is pivotal in the fields of material and biomedical sciences, (ii) our methodology provides an effective blueprint for the initial screening of biomedical materials, and (iii) electrospun PCL/PEG antibiotic-bearing scaffolds exhibit outstanding results in promoting neoangiogenesis and facilitating in vivo wound treatment.

Recycled PET/PA6 Fibers from Waste Textile with Improved Hydrophilicity by In-Situ Reaction-Induced Capacity Enhancement.

Due to the increasing amounts of textile waste, textile to textile recycling is of prime concern. Polyethylene terephthalate (PET) represents the most extensively used type of chemical fiber. Its spinnability suffers from impurities and degradation in the processing, which limits its recycling to new fibers. Here, recycled polyester is blended with a small amount of recycled nylon, and the regenerated fibers, which demonstrated good mechanical properties, were obtained via a melt spinning machine. The mechanical properties, thermal properties, rheological properties, and chemical structure of the modified recycled fibers were investigated. It was found that when compared with rPET-T fibers, the elongation at break of rPET-Ax fibers increased to 17.48%, and the strength at break decreased to 3.79 cN/dtex. The compatibility of PET and PA6 copolymer were enhanced by copolymers produced by in-situ reaction in the processing. Meanwhile, the existence of PA6 increases the crystallization temperature and improves the hydrophilicity of the fibers. This study realized the high-value recycling of waste PET fabric to new fibers, which opens a door for the large utilization of waste textiles.

Approaching Technological Limit for Wet‐Pulling Technique

Carbon nanotube fibers (CNTFs) are a promising economical replacement material for contemporary metallic wired conductors due to their lightweight and advanced electromechanical properties. The wet‐pulling technique for CNTF manufacturing is highly versatile, adaptable for both laboratory as well as industrial‐scale production, and can be optimized for the maximum enhancement of electrophysical properties. Herein, a mechanosolvent‐based postfabrication approach for maximizing densification and improving electrical properties of wet‐pulled CNTFs is examined. The experimental process results in fibers achieving 60% of the theoretically maximum density and conductivity of maximally densified metallic single‐walled carbon nanotube bundles. The technique allows a corresponding increase of ≈700% in fiber density (from 100 to 704 kg m−3), a simultaneous ≈530% increase in electrical conductivity (from 748 to 3990 S cm−1), and reduced volume defects from 18% to 2%. The approach was combined with a step‐wise microstructure monitoring using focused ion beam–scanning electron microscopy to determine the mechanisms behind the optimized structures. This work is the first to provide an experimental and theoretical base for the postfabrication optimization of wet‐pulled CNTFs and lays the foundation for further enhancement with techniques such as chemical doping, fiber compounding, and combined infiltration/densification mechanisms.

Diffusion coefficients during regenerated cellulose fibers formation using ionic liquids as solvents: Experimental investigation and molecular dynamics simulation

Regenerated cellulose fibers (RCFs) are an essential type of bio-based chemical fibers. The preparation of RCFs using ionic liquids (ILs) as solvents is an efficient utilization of ecological resources. Investigating the diffusion coefficients during RCFs formation using ILs as solvents is vital due to the potential impact of the interaction between ILs and coagulants on the morphology and properties of RCFs. The determination of diffusion coefficients during RCFs formation is challenging due to its instantaneous and simultaneous nature. For this research, the method and apparatus for measuring the diffusion coefficients during RCFs formation were established, and the diffusion coefficients of various IL and coagulant systems were also explored under different formation conditions. In addition, the relationship between the diffusion coefficient, the formation condition and the self-diffusion coefficient of ILs were investigated using numerical simulation and molecular dynamics simulation. The results demonstrated that the formation conditions, particularly the temperature and composition of coagulants, significantly impact the diffusion coefficient. Lowering the temperature of the coagulants and incorporating ethanol with lower polarity reduced the diffusion coefficient. The diffusion coefficient of 1-ethyl-3-methylimidazolium diethylphosphate ([Emim]DEP) in the ethanol coagulation bath was 0.79 × 10−9 m2·s−1 at 293 K, which was nearly twice as small as that in the water coagulation bath. These findings were validated by molecular dynamics simulations. Modifying the formation conditions can regulate the structure and properties of the RCFs by affecting the diffusion coefficients during RCFs formation.

A Review on Composite Materials Reinforcing with Organic/ Natural Materials

The utilization of natural and fiber-reinforced polymer matrix composites as a sustainable solution in the industries. The composite consists of sugarcane bagasse and mesquite fibers. which offers a low-cost, environmentally friendly alternative with potential applications in various industries. epoxy resin known for its cost-effectiveness and resilience, serves as the matrix material. Types of fabrication methods are Vacuum Bag Molding, Hand Lay-Up, Filament Winding, and Hydraulic compression molding from the literature we collected Hydraulic compression molding technique with varying fiber orientations (uniaxial, biaxial, and triaxial) is selected for its versatility and reduced material waste. The study involved alkaline, potassium permanganate, and potassium dichromate treatments. The overall study concludes the promising potential of using bagasse and mesquite fibers as sustainable alternatives for reinforcement in epoxy resin composites, offering a viable solution for valorizing agricultural waste and promoting environmentally conscious manufacturing practices. Chemical treatments and fiber processing play a crucial role in enhancing the properties of the fibers, making them suitable for composite applications.