Hasil untuk "Textile bleaching, dyeing, printing, etc."

Benjamin Eghan, Kyungeun Sung

Purpose: This study aims to investigate and characterise the fashion and textile (FT) waste stream in Accra, Ghana. Specifically, it focuses on identifying significant sources of FT waste, current management practices, and the potential of upcycling. As the global fashion industry increasingly addresses sustainability challenges, understanding localised waste patterns is crucial for developing effective, circular, and sustainable interventions tailored to the needs of the developing world. Methodology/Design: Employing a qualitative approach, semi-structured interviews were conducted, utilising snowball sampling to recruit 11 participants who are experts and key stakeholders in the fashion, waste management, and sustainability sectors in Accra. In-depth data were collected through online interviews conducted via Microsoft Teams and WhatsApp, with all sessions audio recorded. The data were analysed with NVivo software, enabling systematic thematic coding and interpretation. Participant interviews were supplemented with government reports and academic literature, triangulating the data to provide a broader context. The study received ethical approval from De Montfort University (DMU) and followed DMU's research ethics policy, including obtaining informed consent from all participants. Findings: Initial findings reveal that the FT waste stream in Accra is primarily driven by imports of second-hand clothing, surplus from local production, and inadequate waste sorting. Participants emphasised the lack of formal infrastructure (e.g., dedicated textile recycling centres), limited public awareness, and weak enforcement of relevant policies. However, there was consensus on the emergence of community-led movements/initiatives focused on upcycling and reuse. The findings also suggest growing awareness of the economic and environmental benefits of reducing textile waste by creating valuable products. Practical and Social Implications: This study provides policymakers, environmental organisations, and social entrepreneurs with actionable strategies to improve the sustainable management of FT waste. Furthermore, it raises social awareness by highlighting how community-driven solutions and active stakeholder engagement can foster eco-innovation and advance circular economy practices in urban Ghana. Originality: The study addresses an important research gap by presenting one of the first qualitative analyses of the fashion and clothing waste context in Accra. By integrating local perspectives with global sustainability discourses, it offers a unique contribution to the field. Its emphasis on upcycling and the inclusion of diverse stakeholder voices enhances its originality, positioning it as a valuable addition to both theoretical and practical research on sustainable fashion and waste reduction in sub-Saharan Africa

Ekkarin Phongphinittana, Navapon Klangtup, Petch Jearanaisilawong

The study evaluates the mechanical properties of a woven bamboo structure made from bamboo strips using an analytical relation and finite element simulation. The bamboo studied is a recently discovered species, Bambusa Nghiana, characterized by long internodes. Bamboo strips have lower strength at the node junctions, a feature that can be advantageous for this species due to its extended internode length. Plain weave bamboo structures were handwoven from thin, rectangular bamboo strips cut from the bamboo culm along the radial direction. The high bending rigidity of the bamboo strips resulted in an asymmetric woven structure with curved warp strips and straight weft strips. The stiffness of the woven structure was correlated with the stiffness of the bamboo strips and the weave geometry. The in-plane shear resistance of the woven structure was significantly lower than its axial stiffness due to the asymmetric weaving. These in-plane properties were validated using finite element simulation through a user subroutine incorporating the woven structure and the Hashin damage criteria. The prediction of the puncture simulation showed good agreement with the corresponding experiment. These results confirm the proposed analytical relation between the mechanical properties of individual bamboo strips and those of the woven structure.

Bozena Burtan-Gwizdala, Jan Cisowski, Radoslaw Lisiecki et al.

This study examined spectroscopic, thermal, and other qualities, such as the lasing parameters, of Sm³⁺-doped glass with the composition 40P₂O₅–30ZnO–20LiCl–10BaF₂. The ellipsometric data were used in a Sellmeier dispersion relation to estimate the refractive index values of the glasses investigated. The measured absorption spectra of the doped glass reveal the presence of various absorption bands assigned to transitions from the ⁶H_5/2 ground state attributed to Sm³⁺-ion-excited states. We studied the decay of the ⁴G_5/2 level of the Sm³⁺ ions in the doped glass by analyzing its absorption and emission fluorescence spectra. The Judd–Ofelt hypothesis allowed us to determine that the quantum efficiency of the ⁴G_5/2–⁶H_7/2 transition is high: 96% and 97% for glass doped with 4.05 <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>×</mo></mrow></semantics></math></inline-formula> 10¹⁹ ions/cm⁻³ and 11 <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>×</mo></mrow></semantics></math></inline-formula> 10¹⁹ ions/cm⁻³, respectively. Furthermore, this glass exhibits efficient red/orange enhanced spontaneous emission that matches the excitation band of the photosensitizer material used in medical applications.

Anand Palanivel, Karthik Palanivel, Robert Cep et al.

Natural fibers have in recent times turned into reasonable to automotive production as a substitute corroboration for synthetic fiber reinforced thermoplastics. This research was motivated by evolving and assessing benzoyl-treated Neem and Pineapple fiber reinforced and particulated by sawdust in hybrid epoxy polymers for automotive. Seven types of composites were fabricated using hand layup technique. The prepared composites were cut according to their ASTM standard. The Hybrid Neem and Pineapple Fiber Reinforced with Saw dust Particulated Epoxy Composite (NPFRSPEC) was studied for thermal analysis like Thermal Conductivity (TC), Coefficient of Linear Thermal Expansion (CLTE), Heat Deflection Temperature (HDT) and Thermal Gravimetric Analysis (TGA). Morphological analysis was done through FESEM on failure surfaces. The results reveal that treatment fibers enhanced the thermal stability among the non-treated composite. The treated fibers exhibited 10% increase in heat deflection temperature and 28% increase in thermal conductivity. From the results, it’s also noticed that the treated hybrid composite delivers better thermal efficiency when compared with other natural fiber-reinforced polymers available in the sector which could potentially replace long fiber reinforced thermoplastic components in car doors and bumpers.

Vlahović Milica, Vušović Nenad, Vlahović Miljan et al.

The textile industry is a significant global water consumer, generating wastewater laden with pollutants such as dyes, organic compounds, detergents, and heavy metals. The safe disposal and treatment of these effluents are critical to mitigating severe environmental threats, including pollution of water bodies and health risks to humans and aquatic life. This paper reviews various methods for treating textile wastewater, focusing on the ecological and regulatory demands for sustainable water management. Traditional treatment approaches, often insufficient, have driven the exploration of advanced and integrated wastewater treatment technologies. Key methods include physical, chemical, and biological treatments, alongside emerging techniques like membrane filtration, activated carbon adsorption, and advanced oxidation processes (AOPs). AOPs, particularly, off er high efficiency in removing non-biodegradable organic pollutants, making them a promising solution for the textile industry. This comprehensive review underscores the need for innovative, cost-effective, and eco-friendly treatment strategies to ensure sustainable operations and compliance with environmental standards.

K.P. Indulekha, P.K. Jayasree, K. Balan

Cocolog groynes are new form of soft stabilization method, which can be used for restoration of river meanders. After an extensive literature review, it was observed that conventional impermeable groynes behave in a different manner compared to the cocolog groynes which are permeable in nature. Hence, the objective of the present study was to analyze the effect of significant geometrical and hydraulic properties of cocolog groynes on scour and flow patterns in meandering channels. The experimental studies were conducted in a scaled physical model of meandering channel with series of cocolog groynes installed at aspect ratios between 2 and 4, density ratios between 0.12 and 0.18, relative lengths between 0.14 and 0.2 and for orientation angles from 30º to 150º. The desirable range of these parameters for cocolog groynes in meandering channels were obtained as 2.5 to 3.0, 0.14 to 0.16, 0.16 to 0.18 and <90º, respectively, after analyzing the bed scour and dimensionless mean velocity in both streamwise and transverse directions. The study provides an appropriate layout of an eco-friendly soft river bank stabilization technique, which not only promotes vegetation but also restores the river banks.

Ye-eun Woo, Kyung Wha Oh

Abstract The thermal storage and washing durability of polyester fabrics treated with tungsten bronze nanorods(TBNRs) were analyzed to determine the optimal concentration for the photothermal effect in this study. TBNRs with an average length of 34.0 ± 2.5 nm and a diameter of 2.3 ± 0.4 nm were synthesized by the thermal decomposition of Ammonium metatungstate hydrate(AMT) in oleylamine (OA) to generate TBNRs that are capable of emitting heat by efficiently absorbing light in the near-infrared region. The effect of TBNR concentration and the silane coupling agent on the photothermal effect and washing durability of the PET fabric were evaluated with a solar simulator. As a result, as the concentration of TBNRs increased, the photothermal effect increased, and the maximum photothermal effect was shown at 5 wt%. In addition, washing durability were further improved by adding 0.5 wt% silane counpling agent. Overall, the post-processing treatment effectively increased the photothermal effect without a significant change in the physical properties and color of the polyester.

M. K. Sayida, Sheela Evangeline, Akhila Vijayan et al.

Coir fiber is a natural fiber extracted from the husk of coconut. Coir geotextiles made from coir fibers which are biodegradable and eco-friendly are a good alternative to polymeric geotextile. Biodegradation is a factor which limits its civil engineering applications. Hence this study is made to explore the degradation rate of coir geotextiles embedded in different soils. Coir geotextiles composed of lignocelluloses fiber found to be more durable compared to other natural geotextiles. Coir geotextiles improves the CBR values of subgrades, reduces the settlement and are effective in road pavements. But in some soil conditions, coir was powdered or decayed off. In this study, coir geotextile used in field study is embedded in five different types of soil having different compressibility characteristics and chemical constituents. The soil used in the study is collected from different test sites. . Laboratory studies were conducted and rate of degradation is reported. The embedment period is varied from 0 to 135 days. The degradation rate is evaluated by conducting wide width tensile strength test and CBR test using coir samples before and after embedment. The surface morphological characteristics of raw and degraded coir samples and chemical analysis of soil samples are also reported. From the study it is clear that coir geotextile embedded in soil from road 3 with clay of high compressibility degraded at a slower rate compared to other soils.

Sivasubramanian Palanisamy, Mayandi Kalimuthu, Alavudeen Azeez et al.

The contribution of natural lignocellulosic fibers to the reduction in wear damage in polymer resins is of interest, especially when two of these fibers can combine their respective effects. Wear properties of hybrid kenaf/banana epoxy composites have been investigated using three different total amount of fibers, 20, 30 and 40 wt.%, at loading forces up to 30 N and to sliding distances of up to 75 m. This demonstrated that the introduction of the highest level of fibers proved the most suitable for consistency of results and containment of wear with increasing load, as was also found from the morphological evaluation of wear degradation using scanning electron microscopy (SEM). Subsequently, tensile, flexural and impact properties of as-received and post-water-saturation hybrid composites were examined. The tests revealed a limited reduction in tensile and flexural strength, not exceeding 10% of the initial values, which were very high compared to similar materials, almost reaching 140 MPa for tensile strength and exceeding 170 MPa for flexural strength. In contrast, a higher standard deviation of values was found for impact strength, although the decrease in average values was only slightly above 10%. The results suggest the availability of these hybrids for wear-resisting applications in high-moisture environments, and the even more limited water absorption conferred by banana fibers added to kenaf ones.

Albert Serra, Marc Delgado-Aguilar, Ramon Ripoll et al.

The flexural strengths of composite materials composed of polypropylene reinforced with cotton fibers recycled from textile waste are presented. Materials with and without coupling agents were prepared. The analysis of the flexural strength of the specimens showed promising properties, both, in the case of the coupled and uncoupled materials, showing their ability to substitute glass fiber reinforced composites. The presence of dyes in the recycled fibers had a noticeable impact on the properties of the composite. A micromechanics analysis showed that the interphase between the matrix and the reinforcements was stronger than expected for uncoupled materials and weaker than expected for coupled ones. The presence of dyes in the fiber surface had a positive effect by decreasing the hydrophilicity of the fibers, and at the same time inhibited the full exploitation of the coupling agents.

Mohan Turup Pandurangan, Krishnan Kanny

The objective of this work is to improve the thermal properties of natural fibers by infusing thermally stable alumina-silicate clay nanoparticle into the fibers by physical infusion method. Four commonly used natural fibers were selected, namely, banana, coir, kenaf, and sisal fibers. Nanoclay particles were infused into these fibers at untreated and mercerized (NaOH-treated) stages. The distribution of nanoclay on fiber surface is examined by using scanning electron microscope (SEM). Nanoclay distribution is better in NaOH-treated fiber when compared with untreated fiber. Thermal properties such as mass loss, thermal decomposition, and flame retardance was evaluated for all fiber series. Thermal degradation kinetics of untreated and treated fiber series is examined by using Coats-Redfern method. The outcome of the result shows that the thermal properties of nanoclay infusion in NaOH-treated fibers are fairly consistent across all types of tested fibers. Nanoclay infusion into the fibers improved mass gain, decomposition, and flame retardance properties.

R. Gopinath, P. Billigraham, T.P. Sathishkumar

This study deals with the extraction and characterization of novel cellulosic fiber extracted from the bark of Markhamia lutea tree. The chemical constituents of fibers such as 66.41 wt.% of cellulose, 6.36 wt.% of hemicellulose, 7.82 wt.% of lignin, 0.41 wt.% of wax and 9.06 wt.% of moisture were identified. The functional groups present in the fibers were examined through Fourier transform infrared spectroscopy. The crystallinity index and crystallite size of fibers determined using X-ray diffractogram are found to be 71.77% and 2.07 nm. Lower density (1050 kg/m3) and high tensile strength (835.72 ± 197.05 MPa) makes MLF reinforced polymer composites ideal for lightweight applications. Thermal degradation behavior of the fiber investigated through thermogravimetric, derivative thermogravimetric and differential scanning calorimetry revealed the beginning of initial thermal degradation at 244°C, and this makes them suitable for making green composites.

Roberto Giannuzzi, Vitantonio Primiceri, Riccardo Scarfiello et al.

With the main objective being to develop photochromic smart textiles, in this paper, we studied the photochromic behavior of WO_3-x nanocrystals (NCs) cooperatively interacting with variable amounts of TiO₂ NCs. We tested several blends of WO_3-x:TiO₂ NCs, admixed in different compositions (relative molar ratio of 4:0, 3:1, 2:2, 1:3, 0:4) and electrostatically interfacing because of opposite values of Z-potential, for photo-induced chromogenic textiles. We further monitored the photochromic sensitivity of NC-impregnated textiles after exposure to a few solvents (i.e., methanol, ethanol, and isopropanol) or when over-coated with different polymeric matrices such as natural cellulose or ionic conductive Nafion. The optimization of the compositions of the WO_3-x:TiO₂ blends embedded in polymeric matrices, allowed the nanostructured photochromic textiles to show rapid and tunable coloration (<5 min) and bleaching kinetics (~5 in at 75 °C or 6 h at room temperature) along with good recovery and cycling stability. This study features a simple strategy for the widespread application of WO_3-x:TiO₂-based photochromic smart textiles.

Shakila Bano, Vineeta Singh, A. Hashmi et al.

Brilliant green (BG), one of the triphenylmethane dyes, has been extensively applied and produced as a colorant for different industries like medical, paper/textile printing, food additive, cosmetics, etc. Dyes effluents discharged by these industries pose hazardous effects on environmental and human health via releasing toxic and carcinogenic contaminants during its deterioration. The present work evaluates kinetic and mechanistic aspects of oxidative degradation of brilliant green by iodate in acidic solution at 303 K. The influence of different factors such as concentration of various reactants (μ), free radicals, etc. has also been investigated to check feasibility of redox degradation for efficient, easy, low-cost and eco-friendly removal of brilliant green from aquatic medium. The experimental result shows a first-order rate dependence on [BG] and zero-order kinetics with respect to [KIO3]. The reaction showed positive fractional order dependence on the rate for [H+]. Variations in ionic strength of the medium and [Cl–] did not bring about any noticeable change on the rate of reaction. It was found that the reaction rate declined with the decrease in the dielectric constant (D) of the medium in the oxidation of brilliant green. Additionally, the process was carried out at different temperatures to estimate the activation parameters and also to find rate controlling stages of the process. Finally, an appropriate mechanism, a plausible with the experimental observations, also supported by UV-Vis spectra has been proposed.

Faisal M. Almutairi, Yassine El-Ghoul, M. Jabli

Cellulose is the most widely available biopolymer which is extensively used for several applications including textiles, composites, pharmaceutical, water treatment, etc. In this investigation, cellulose was chemically extracted from Populus tremula seed fibers. Samples were characterized using FT-IR, SEM, XRD, and TGA-DTA analyses. FT-IR spectrum of the extracted cellulose confirmed that hemicellulose and lignin were removed during alkali and bleaching treatments. SEM images showed the partially roughened surface of the fiber due to the removal of non-cellulosic elements and surface impurities during chemical modification. The crystallinity index values for untreated Populus tremula fibers and extracted cellulose were calculated to be 32.8% and 58.9%, respectively. The obvious increase in the crystallinity index for the extracted cellulose confirmed the removal of amorphous compounds present in raw populus. Alkali-treated populus fibers were more thermally stable than raw fibers. All changes observed after alkali and bleaching treatments evidenced the removal of amorphous contents and non-cellulosic components in raw populus fibers. Extracted cellulose exhibited excellent adsorption capacities of methylene blue (140.4 mg g−1) and crystal violet (154 mg g−1). The pseudo second order equation fitted well the kinetic data indicating a chemi-sorption process. The Freundlich model complied well with the experimental data suggesting that the adsorption of the studied dyes was multilayer.

J. Rippon, David J. Evans

Abstract: In general, the properties of synthetic fibres can be engineered to suit different end-uses when the fibres are manufactured. Natural fibres, however, require various treatments in order to give them a range of properties suitable for different end-uses. Some of the treatments used are specific for the particular fibre. For example, for wool, processes include steam-setting to give dimensional stability to fabrics, treatments to reduce felting shrinkage and treatments to impart resistance to insect attack. Fibre-specific processes for cellulosic fibres, such as cotton and the bast fibres, include mercerising, which improves properties such as dyeing and lustre, and chemical cross-linking treatments to improve the wrinkle recovery of fabrics. Silk is given treatments to improve appearance retention and to modify handle. Some processes, such as scouring and bleaching, are common to all types of natural fibres, but the different chemical structure of the protein and cellulosic fibres requires very different conditions in order to avoid fibre damage. Although many textile products are coloured by dyeing or printing, the types of dyes and the dyeing methods used on protein fibres differ markedly from those used on cellulosic materials. This chapter describes the various processes used on the natural fibres, together with the underlying chemistry involved in each procedure.

S. Rathinavel, S. S. Saravanakumar

Environmental concerns are raised due to municipal solid wastes especially due to non-biodegradable packaging waste materials. To overcome such issues, researchers gained attention in biodegradable natural waste materials as an alternative to existing non-biodegradable packaging materials. In this work, Orange Peel Powder (OPP) chosen as a filler at varying proportion (5% to 20% of wt.) and polyvinyl alcohol (PVA) used a matrix to prepare biocomposite films by solution casting method. The films were analyzed with FT-IR, XRD, TGA, DSC, and tensile tests. The results of FT-IR and XRD show smooth dispersion of PVA and OPP, whereas samples are thermally stable up to 350°C & tensile properties of the prepared biofilms increased with inclusion of OPP from 6.20 MPa to 7.80 MPa and are better than the conventional-packaging materials which can be used as eco-friendly packaging materials.

C. Corda, Srinivas M. Kini

In this article efficiency of activated carbon as a potent adsorbent of cationic dyes has been reviewed. Non-biodegradable nature of pollutants and their removal in the present generation is a great challenge. Therefore, extensive study on adsorption of these classes of pollutants from water bodies is being carried out. Methylene blue (majorly) a dye seen in the effluent streams of textile, printing, paper industries along with some of the commonly used cationic dyes in process industries and their sorption on activated carbon are reviewed here. High cost of commercially activated carbon which is a limitation to its extensive use have paved way for study of adsorption by naturally obtained and extracted activated carbon from agricultural wastes and various other sources. The purpose of this review paper is to summarize the available information on the removal of cationic dyes using naturally extracted and commercially obtained activated carbon. Various parameters such as temperature, initial dye concentration, pH, contact time, adsorbent dosage, particle size, stirring, agitation etc. were studied and the optimum parameters were determined based on the experimental outcomes. Equilibrium data was examined using Langmuir, Freundlich, Temkin and Dubinin–Radushkevich and few other isotherm models. Kinetic studies also have been carried out to find the most suitable way of expressing the adsorption process.

Anirban Dutta, Biswapati Chatterjee

Abstract Embroidery through computer aided semi-automatic machines is one of the most widely used option for the surface ornamentation of apparel fabrics at present. Since the embroidery process includes addition of certain amount of embroidery-threads depending upon the design motif, it is quite obvious that basic physical and functional properties of fabric are subject to change. It is therefore important to develop an algorithm or empirical equation for proper prediction of the properties of the embroidered fabric, relevant to its required end-use in apparel industry. In this context, an effort has been made to determine a prediction equation through linear multiple regressions for the prediction of longitudinal stiffness of embroidered fabric in terms of flexural rigidity in warp direction of the base fabric, considering the input parameters as warp-way flexural rigidity of the base fabric, breaking load and linear density of the embroidery thread, stitch density, average stitch length and average stitch angle of the embroidery design. The final Prediction model is statistically verified taking new embroidery samples of different varieties. It is found that the model can predict with a very satisfactory level of accuracy. Also, the influences of the embroidery parameters in this context have been analyzed through the corresponding regression coefficients and the three dimensional (3D) surface curves. Stitch density has been emerged as the most influential parameter, followed by the stitch length and the stitch angle.

Boakye Andrews, Raji Rafui King, Ma Pibo et al.

This research investigates the compressive property of a novel composite based on a weft-knitted auxetic tube subjected to a quasi-static compression test. In order to maximize the influence of the fiber content on the compression test, a Kevlar yarn was used in knitting the tubular samples using three different auxetic arrow-head structures (i.e. 4 × 4, 6 × 6 and 8 × 8 structure). A quasi-static compression test was conducted under two different impact loading speeds (i.e. 5 mm/min and 15 mm/min loading speed). The results indicate that the energy absorption (EA) property of the auxetic composite is highly influenced by the auxeticity of the knitted tubular fabric.