Semiha Eren

The hydrophobic nature of polyester fibres and their low moisture regain limit their dyeing process with natural colorants. Therefore, to enhance the surface wettability of the fabrics and improve dye affinity, surface modification pre‐treatments using ultraviolet (UV), ozone (O ₃ ) and a combination of UV/O ₃ were applied. The chemical and morphological changes in the fabrics were evaluated using Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) analyses, respectively. All samples were dyed with madder as a common natural dye. Post‐dyeing performance tests, such as colour strength, tensile strength, water vapour permeability, air permeability and overall moisture management capacity (OMMC), were conducted on the samples. The results demonstrated that both UV and O ₃ treatments significantly improved the dyeability of the fabrics and their moisture management properties. The highest colour strength value for O ₃ ‐treated samples was obtained with a gas flow rate of 15 L/min and an ozonation time of 90 min, while for UV treatment, the highest colour strength was achieved at a lamp distance of 21 cm with an irradiation time of 120 min. In the combined treatment trials, the highest colour strength value was achieved with UV, followed by O ₃ treatment; however, mechanical strength was further reduced. FTIR analysis confirmed the formation of new functional groups, and SEM images revealed surface etching and an increase in roughness. These findings reveal the potential of these environmentally friendly physical modification methods to enhance the dyeability of polyester fabrics with natural dyes.

This research examined the impact of ozone surface alteration on the dye absorption of Tencel textiles using natural dyes devoid of mordants. Fabric specimens received ozonation at two distinct gas flow rates (5 L/min and 15 L/min) for two different durations (30 min and 60 min) before being dyed with madder and barberry root dyes. Dye uptake, oxycellulose content, color properties, and staining-based fastness of the dyed fabrics were examined. Chemical and morphological changes were characterized by FTIR and SEM analyses. The results revealed that ozone surface modification altered the surface properties of the fabrics, leading to an increase in dye uptake and an improvement in color strength. For both natural dyes, the highest color yield was observed at the ozonation condition of 15 L/min for 30 min. Under optimum conditions, the maximum K/S value was determined as 1.61 for madder dyeing and 3.28 for barberry root dyeing. Furthermore, it was determined that the mechanical and staining-based fastness properties of the fabrics remained within acceptable limits under the selected optimum conditions. This enhancement is consistent with the increase in surface roughness observed in SEM analyses and the formation of oxygen-containing functional groups identified in FTIR spectra. The morphological irregularities formed on the fiber surface as a result of ozone treatment increased the effective surface area, while the increase in carbonyl and hydroxyl groups enhanced fiber polarity, thereby strengthening the intermolecular interactions between the dye and the fiber. The research findings show that ozone-based surface modification is an environmentally friendly pretreatment method that reduces chemical consumption while improving the dyeability of cellulose-based fabrics with natural dyes, and holds promise for future sustainable textile applications and natural dyeing research.

The development of bioactive surgical sutures capable of delivering therapeutic agents directly at the wound site has gained increasing attention in biomedical research. Functionalized sutures may provide localized antimicrobial or anti-inflammatory activity, potentially reducing postoperative complications and promoting tissue healing. In this study, absorbable surgical sutures were impregnated with carvacrol, a natural phenolic compound with well-known antimicrobial properties, using supercritical carbon dioxide (scCO₂) technology. The impregnation process was carried out at 35 °C and 10 MPa for 120 min, allowing for the incorporation of carvacrol into the polymeric matrix of the sutures. The in vitro release behavior of the impregnated sutures was evaluated in phosphate-buffered saline (PBS, pH 7.4) at 37 °C over an 8-day period. The concentration of released compounds was determined by UV–Vis spectrophotometry using previously established calibration curves. An analysis of the experimental release data demonstrated that both carvacrol and benzydamine hydrochloride (HCl) (Tantum Verde^®) exhibited a sustained release profile throughout the incubation period. Carvacrol release increased progressively from 2.02 ± 0.15 ppm on day 1 to 7.45 ± 0.15 ppm on day 7, followed by a slight stabilization on day 8 (7.25 ± 0.31 ppm). Similarly, benzydamine HCl (Tantum Verde^®) release increased from 1.83 ± 0.11 ppm on day 1 to 3.29 ± 0.13 ppm on day 8. Release kinetics were analyzed using the Korsmeyer–Peppas model, indicating that the release mechanism was predominantly diffusion-controlled during the initial stage of the experiment. The results demonstrate that supercritical CO₂ impregnation is an effective solvent-free technique for incorporating bioactive compounds into absorbable sutures, enabling controlled release under physiological conditions.

In this study, a UV surface modification method was applied to polyamide (PA) fibers, and its effect on certain fresh and hardened properties of fiber-reinforced cementitious systems was investigated. Within the scope of the study, the individual and interactive effects of fiber volume fraction and UV surface modification time were optimized using the Response Surface Methodology (RSM) based on Central Composite Design (CCD). The optimal performance parameters with CCD were identified at 0.50% fiber content and 18 min of UV exposure. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) were utilized to analyze the fibers and examine the impacts of surface modification. Three different sample groups were prepared to test the effect of UV treatment after optimization: a control cement mortar without fibers, a polyamide fiber-reinforced mortar without UV treatment, and a polyamide fiber-reinforced mortar with UV surface modification. The tensile, flexural, and compressive strength values of the specimens were determined. The results indicated that UV surface modification led to changes in fiber roughness and an increase in oxygen-containing functional groups on the fiber surface. The data revealed that the mechanical performance of fiber-reinforced composites subjected to surface modification improved (with a 27.4% increase in flexural strength and an 11.3% increase in compressive strength compared to the control samples). The findings indicate that UV surface modification improves the fiber–matrix bond in cement-based systems reinforced with polyamide fibers. UV surface modification emerges as an effective and environmentally friendly method for enhancing the performance properties of fiber-reinforced cement-based systems.

The increasing demand for functional textiles has led to extensive research on the incorporation of mineral-based additives into synthetic fibers to enhance their performance characteristics. In this study, the effects of volcanic mineral additives on the mechanical properties of polyester yarns and woven fabrics intended for solar protection applications were investigated. Cerium oxide-and silicon oxide-based masterbatches were prepared using a PBT carrier and incorporated into polyester during the melt-spinning process to produce partially oriented yarns (POY). The POY yarns were subsequently textured to obtain draw textured yarns (DTY), which were then used in the production of curtain fabrics. The tensile properties, boiling shrinkage, and crimp contraction behaviour of the yarns were evaluated, while the mechanical performance of the woven fabrics was assessed through tensile strength and tear strength tests conducted in both warp and weft directions. The results demonstrated that the incorporation of volcanic mineral additives influenced the structural and mechanical behaviour of polyester yarns and fabrics. Fabric test results revealed that cerium oxide-added polyester fabrics exhibited higher breaking strength values than silicon oxide-added fabrics. Tear strength performance was affected by both fabric direction and additive type. While fabrics containing 2% silicon oxide showed lower tear strength in the warp direction, they exhibited higher tear strength in the weft direction. Overall, the findings demonstrate that volcanic mineral additives can be successfully incorporated into polyester yarn structures and significantly influence the resulting yarn and fabric properties.

In this study, the bleaching of interlock knitted fabric using an innovative and environmentally friendly method involving ozone gas was explored. The bleaching processes were conducted under varying conditions: different pH levels (pH 7 to pH 12), ozone gas flow rates (2 L/min to 6 L/min), and ozonation durations (20, 40, and 60 minutes). Fabrics treated with ozonation were compared to those subjected to conventional bleaching methods. Assessments of the samples were performed for whiteness, bursting strength, color measurements, and fastness properties. Additionally, Chemical Oxygen Demand (COD) tests were conducted on wastewater from both conventional bleaching and ozonation processes. Optimal conditions were determined to be at pH 7, with a 6 L/min ozone flow rate, and a 60-minute duration. Under these conditions, the whiteness index reached 80 Stensby, and the yellowness index was 7.6. Furthermore, a reduction of approximately 90 % in COD values was observed, indicating a significant decrease in environmental impact. However, a decrease of about 30 % in burst strength was also noted. This study highlights the potential of ozone technology to replace traditional chemical-intensive methods, offering a more sustainable solution for the textile industry.

This study investigates the successful removal of color from wastewater generated during the dyeing of widely used viscose fabrics in the textile industry using the advanced oxidation process, UV/ H2O2. Subsequently, the usability of these treated waters for repeated dyeing is examined. No chemicals other than the dye were added during the dyeing process. The results demonstrate that viscose samples can be dyed successfully up to the 3rd cycle without any significant loss in color difference and fastness values. While no change in pH values was observed until the 7th cycle, there was a decrease in conductivity values, resulting in the samples being dyed in progressively lighter colors. No significant losses in fastness and strength were detected in the samples until the 7th cycle. The textile finishing industry is known for its high water consumption and pollution, contributing to a rapid decrease in accessible clean water resources. This wastewater is discharged into the environment, posing significant environmental challenges. According to the findings of this study, the ability to reuse the same water for up to 3 cycles can offer substantial advantages in terms of both the environment and cost savings.

Tekstil, hammaddeden başlayıp son ürün elde edilene kadar hemen hemen her adımda çıkan ürüne test yapılan bir alandır. Artan dünya nüfusu ile birlikte tekstil sektörü alanında araştırmalar yapan kişiler ve firmalar yeni ürünler üretmek için sürekli araştırmalar ve analizler yapmaktadır. Yapılan bu analizlerde büyük bir veri kaynağı oluşturmaktadır. Bu amaç doğrultusunda da Demirtaş Organize Sanayi Bölgesi’nde yer alan bir havlu firmasından alınan veriler kullanılarak bir veri seti oluşturulmuştur. Veri setinde havlu kumaşlara uygulanan testlerden olan kopma mukavemeti, hidrofilite ve hava geçirgenliği test sonuçları kullanılmıştır. Oluşturulan veri setine uygun makine öğrenmesi regresyon modelleri sunulmuştur. Elde edilen tahmin analiz sonuçlarına göre kopma mukavemeti ve hava geçirgenliği sonuçlarında SVM modeli, hidrofilite sonuçlarında Random Forest en iyi R2 skor performansı göstermiştir. Bulgular kopma mukavemeti, hidrofilite ve hava geçirgenliği değerlerinin makine öğrenmesi modelleri ile tahmin edilebileceğini sunmaktadır.