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ABSTRACTTechnologies like bunch covers have been shown to improve quality of date fruits. It is one of the approaches which are believed effective to protect the most sensitive stage of date fruit from autumnal rain and carob date. An experimental procedure is set up to allow farmers to predict, analyze, and optimize cover bunch performance after its use in protection applications and to select the ideal bag. The cover quality is designed based on a mathematical model and further optimized using MINITAB. From this analysis, the impact of each individual parameter on the desired response parameters has been studied. The results proved that the best cover could be found in optimal conditions. Using the influential parameters as tear strength, tensile strength, weight, air permeability and resistance to water penetration, the results indicate that the cover bunch remains influenced after harvesting period by the resistance to water penetration properties and tear strength as well.

Recognizing the importance of using plant fibers in polymeric composites and the no availability of data on fine structure, physico-chemical, morphological and others properties of Typha Angustata stem fibers, a study was undertaken with the objective of determining some of these properties. In this work, untreated and treated Typha stem fibers by NaOH treatment have been extracted and characterized to evaluate and compare their surface condition as well as their chemical composition, their fine structure and their mechanical properties. Typha stem treated fibers (TSTFs) have presented best results with an alpha-cellulose content of 51.3%, a density of 1460 kg/m3, an average tensile strength equal to 9.42cN/tex and a diameter of 208.12 µm. Also, Crystallinity Index (CI) of TSTFs was 57.4%. Unsaturated polyester matrix was reinforced with TSTFs and mechanical properties were undergone. Results show that TSTFs could be used for sustainable fiber-reinforced polymer composites with an enhancement in flexural and tensile tests for 12.6% TSTFs ratio.

Water injury and fungus infection are the main causes of large economic deterioration and losses in the quality of date fruits during harvesting period. The nonwoven bagging product was used for the first time on date palm and has been shown to efficiently protect date fruit from heavy rain and sunburn that reduces the rate of transpiration and increases fungus spoilage. The aim of this study is to evaluate the potential applicability of COMSOL code in simulating the heat transfer behavior through nonwoven date cover. The study also intended to use finite element method and adaptive mesh refinement technique to increase the accuracy of the solution and create model for efficient simulation of heat exchange in nonwoven bag. The proposed model was validated by the uniformity between simulating and experimental results. A detailed numerical study was conducted to find the influence of air permeability on heat transfer through nonwoven textiles. Results demonstrated that the reduction of nonwoven permeability is beneficial to minimize the heat taken away by forced convection by decreasing the inner air transportation.

The kenaf fibers were used to reinforce composites with two structures: nonwoven and bulk fibers and with treated and untreated kenaf fiber. A series of tensile tests were conducted on these composites. The use of kenaf fibers allows having composite with improved mechanical properties compared to pure polyester composite. This increase reaches 56.15% in strength and 137.85% in strain when varying the fiber weight ratio and the reinforcement structure. The interested results for both tensile strength and strain are obtained for nonwoven structure made by untreated fiber. The statistical study reveals that the most influencing parameter in tensile properties was the reinforcement weight ratio. The optimum composite was obtained when using a nonwoven structure made with untreated fiber with 11.10% fiber weight ratio.

According to environmental issues and guidelines, increasing efforts are being focused on reducing the harmful impact of textile wastes either by lowering the use of chemicals or by recycling wastes into new products to give them a new life cycle. In this paper, we investigate the physical and chemical properties of wool wastes coming from tanning industry, where the process of pulling the wool from the hide is based on chemical processes. These so-called “’Pulled wool’” properties are compared to virgin raw wool obtained from the same pelt, to evaluate the degradation of the fiber induced by the chemicals. SEM observations indicate that the pulled wool fiber surface appeared rougher, and the scales appeared to have been affected. Based on the X-ray diffraction, the crystallinity of the pulled fibers appeared to have been slightly reduced. Attenuated ATR-FTIR analyses indicated some changes in chemical composition. HPLC tests showed an apparent increase in the amount of cystic acids indicating damage of some macromolecular chains crosslinking. Thus, some properties appeared significantly affected during the chemical unhairing process. Based on these characteristics of pulled wool, potential applications to valorize it could be suggested, as we show that it remains suitable for conventional textile processes.

This paper presents the results of the first kenaf spinning attempt in Tunisia. Indeed, kenaf fibers are rigid and lack of cohesion that makes their spinning difficult and a challenge. So, this paper describes the possibility of spinning different blends of kenaf/cotton fibers using open end spinning machine. Five different blends of kenaf/cotton (M1:10/90, M2:20/80, M3:30/70, M4:40/60, and M5:50/50) were considered. The higher kenaf content in the blend make spinning process difficult and even impossible. The produced yarns were characterized to evaluate their mechanical properties and compare it to similar yarn performances. These blends gave different yarn counts varying from 41.86 to 69.16 tex, tenacity of 8.80 cN/tex to 10.07 cN/tex, while elongation at break of 7% to 8.93%. The results proves that kenaf/cotton 40/60 blend ratio presents the better mechanical properties and regularity with 8.80 cN/tex for tenacity and 7.68% for elongation with good regularity index Ireg = 1.25.

Antimicrobial active sheets based on agave ultimate fibers were prepared by incorporating essential oils (thymol and clove oil) at different concentrations. A complete structural, mechanical, and antimicrobial characterization of treated samples was carried out. SEM proved the presence and the deposit of additives on the surface of the sheet. FTIR spectra confirm the incorporation of essential oils into treated papers. Mechanical properties reveal a decrease in elastic modulus from 31.1 kN/m for raw sheet to 17.8 kN/m for thymol and to 26.7 kN/m for clove oil for treated sheets, and tensile strength from 28.2 N to 24.1 N for thymol and to 14.1 N for clove oil was obtained for the active sheets compared with raw sheets. While the presence of additives increased slightly the elongation at yield of treated samples from 2.3% to 2.6% for thymol and to 2.8% for clove oil. Regarding antibacterial activity, thymol and clove oil showed inhibition against strain present in food. Thymol had the higher inhibition against S. aureus (4.08 cm), and clove oil had the best inhibition against E. coli. (4.13 cm). The obtained results proved that active agave sheets are able to be used as antimicrobial packaging.

In this paper, two extraction methods for kenaf fiber, The chemical process and the enzymatic one, were performed. These processes were used to extract fibers from the kenaf stem and the chemical, mechanical and morphologic properties of the extracted fibers were investigated. We notice that the fiber diameter decrease when increasing the concentration of the enzyme and the time treatment (101,35 µm for Enz1 and 91,37 µm for Enz4) the same result is obtained for the chemical extraction when increasing the duration, temperature or NaOH concentration. Also the fiber crystallinity index is improved due to the elimination of the noncellulosic materials from the fiber. The results obtained show that we have an increase in this index for all treated fiber however it is more important for the chemical extraction (crude fiber 57.39%, chemical-treated fiber 71.93% and 66.70% for the enzyme-treated fiber). This increase explains also the increase of fiber tenacity and the decrease of strain and we found through the tensile test that kenaf fiber has a pure elastic behavior for all treated fiber. So, the properties of extracted fibers compared to the crude fibers prove that the enzymatic extraction preserves more the fiber structure than the chemical extraction.

This study constitutes a comprehensive investigation centred on comprehending the behaviour and characteristics of recycled polyvinyl chloride (PVC) powders. The overarching objective is to successfully conclude the initial research phase, during which PVC-coated fabric offcuts undergo a transformation into PVC powder while achieving complete separation from polyethylene terephthalate fibres. The study entails a qualitative description of the morphology of PVC powder particles, employing an optical microscope to distinguish the diverse shapes exhibited by these particles. The optical microscope observations of PVC powder reveal a distinct array of non-spherical particles characterized by flat, elongated shapes. These high-magnification images unveil the intricate morphological features of the particles, highlighting their irregular shapes. Subsequently, a quantitative analysis of PVC particle size distribution is performed, comparing results from optical microscopy with those obtained through mechanical sieving. The qualitative and quantitative findings obtained provide robust evidence supporting the correlation and confirm that most particles are smaller than 600 µm (93.6%) using an optical microscope and the sieving process (96.39%). The greatest fraction (83.44%) is in the size range between 200 and 600 µm. Assessing flowability, another significant aspect in the evaluation of powders, provides insights into its behaviour and interparticle interactions. The flowability results indicate a Compressibility Index of approximately 26.84%, which suggests poor flowability. This means that the powder is likely to encounter difficulties in flowing freely. This finding is in line with the Hausner ratio, which measures 1.37. This investigation of recycled PVC powder will offer insights into the potential applications and processing considerations of this powder. More concretely, the use of recycled PVC powder shows promise as a viable alternative to conventional PVC resin in plastisol formulations, offering the potential to maintain the properties of the final PVC product without adverse effects. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plant derived natural fibers have been widely investigated as alternatives to synthetic fibers in reinforcing polymers. Researchers over the years have explored many plant fibers using different extraction processes to study their physical, chemical, and mechanical properties. In this context, the present study relates to the extraction, characterization, and optimization of Typha angustata L. stem fibers. For this purpose, desirability functions and response surface methodology were applied to simultaneously optimize the diameter (D), linear density (LD); yield (Y), lignin fraction (L), and tenacity (T) of Typha stem fibers. Typha stems have been subjected to both alkali (NaOH) and enzymatic (pectinex ultra-SPL) treatments. Three levels of process variables including enzyme concentration (10, 15, and 20 ml/L) and treatment duration (10, 15, and 20 days) were used to design the experiments according to the factorial design. Experimental results were examined by analysis of variance and fitted to second order polynomial model using multiple regression analysis. The Derringer's desirability function released that the values of process variables generating optimized diameter, linear density, yield, lignin ratio and tenacity are 20 ml/L and 20 days for concentration of pectinex ultra-SPL enzyme and treatment duration, respectively. Confirmation was performed and high degree of correlation was found between the experimental and statistical values. Moreover, the morphological structure has been investigated by the scanning electron microscope, showing a crenelated structure of ultimate fiber bundles of cellulose composing the Typha fiber. Compared to Typha stem non-treated fibers (TSNTF), Typha stem combined treated fibers (TSCTF), brings to improve mechanical properties. This change in mechanical properties is affected by modifying the fiber structure showing alpha cellulose of (66.86%) and lignin ratio of (10.83%) with a crystallinity index of (58.47%). [ABSTRACT FROM AUTHOR]

Foreign Body Reaction (FBR) is a critical issue when polyester textiles are used as medical implants to perform hernia repair, stenosed artery replacement or aneurysm pathology treatment. Whatever the application, the natural porosity of textile materials tends to induce exaggerated biological tissue in-growth after implantation. This mechanism can prevent the implant from remaining flexible and should be limited. It has been shown in literature that one potential strategy to limit the FBR process is to increase the surface roughness of the implanted material, as fibroblasts proliferate slowlier on irregular surfaces. The purpose of this study was to investigate the potential of modifying the topography of textile surfaces using a particle projection technology. A supercritical N2 jet was used to spray corundum particles on multi-filament PET woven surfaces. The impact of the particles created local filament ruptures on the treated surfaces towards hairiness increase. The influence of the jet projection parameters such as pressure, standoff distance (SoD), particle size and mass flow rate on the textile surface roughness was investigated. Two constructions were considered for comparison purpose (plain weave constructions characterized by 34 and 28 weft yarns/cm). The results show that under certain projection conditions, particles can generate a layer of frayed fibers on the textile surface. It comes out that regular hairiness is obtained on the sample surface with following set up adjustment parameters: pressure of 900 bars, SoD of 400 mm and a particle mass flow rate of 0.6 g/s. The interaction of the treated surfaces with mesenchymal stem cells (MSC) was then assessed in vitro in order to identify how hairiness may modify the adhesion (at 24 h) and the proliferation (at 72 h) of the seeded cells. The results show that the obtained hairiness of treated textile surfaces helps limiting cell proliferation in contrast to non-treated surfaces. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article presents the study of the tensile characteristics of the Typha fiber reinforced polyester composites. Composites have been developed by hand lay-up technique with different Typha fibers treated conditions (sea water, alkali and combined treatment), different volume fraction and reinforcement origin (Leaf or Stem fibers) and structure (mixture of fibers or nonwoven structure). The experimental results indicated an improvement in tensile strength with increasing fiber content. Thus, a maximum tensile strength was observed and was equal to 24.58 and 25.07 MPa, respectively, for a fiber content of 12.6% of the leaf fibers and 10.3% of the typha stalk fibers. Mercerization has successfully modified the structure of fibers and improved the performance of Typha fiber composites by promoting better fiber to resin bonding. Statistical analysis shows that the optimum solution was obtained by using a bulk structure having a rate of 12.6% for the extracted fibers from the chemically treated stems. [ABSTRACT FROM AUTHOR]

This study aims to highlight a mechanical recycling process specifically tailored for PVCcoated fabric waste. While ample information exists on the recycling of pure PVC, a noticeable lack of information regarding PVC-coated fabrics has been identified in the literature. Therefore, the primary challenge lies in accomplishing a thorough separation between PET fibers and PVC powder while simultaneously ensuring the optimal recovery of small PVC particles. This separation is crucial for maintaining the quality and purity of the resulting materials. The effectiveness and efficiency of this process were evaluated through a comprehensive analysis that incorporated qualitative and quantitative studies. For the qualitative study, an optical microscopewas utilized to provide a rapid and non-destructive approach for evaluating the overall properties of the samples. This method provided valuable insights into the shapes, interactions, and cohesive bonds among the different components. In contrast, the quantitative study involved a chemical method that resulted in a destructive process. Using this technique, precise values were obtained, including the exact percentage of each constituent. By integrating the findings from both qualitative and quantitative studies, informed decisions can be made regarding the selection and profitability of the method for achieving a complete separation between PVC powder and PET fibers. The results obtained demonstrated a successful recovery rate of 83.92% for PVC compared with the initial amount. The remaining 16.07% of PVC was found to be either entangled with PET fibers or lost during the grinding process, particularly in the pulverizer machines. [ABSTRACT FROM AUTHOR]

The goal of this research is to see how the amount and particle size of calcium carbonate (CaCO3 ) used in the foamed layer in use for PVC-coated textiles affects the thermal properties of the material. Two different particle sizes were used at various concentrations. The impact of different CaCO3 loadings and particle sizes on the PVC foamed layer’s thermal properties were examined. Thermogravimetry (TGA and DTG) and differential scanning calorimetry (DSC) measurements were utilized to investigate the thermal properties of the PVC foamed layer and the samples have been also characterized by FTIR spectroscopy. According to the findings, the thermal stability of the foamed layer was improved with the addition of calcium carbonate. Through the higher surface area between the filler and the PVC matrix, smaller particle sizes have produced the best results. The PVC foamed layer shows also changes in FTIR spectra after adding CaCO3, and the intensity of peaks increases with decreasing CaCO3 particle size. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Fibers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Carpet resiliency was better for carpets manufactured from engineered yarns. Keywords: Hand-made carpet; compression; contour plots; optimization; resilience EN Hand-made carpet compression contour plots optimization resilience 7382 7390 9 11/21/22 20221220 NES 221220 Introduction Carpets, since BC 5-6th centuries, have been produced due to the demand for a comfortable and warm floor and have an important place in home decoration. Contour plots show that the most preferment carpet are those made with a higher pile yarn linear density (>900 tex) and have a lower pile height (<7 mm). From these plots, we concluded that using pile yarns coarser than 900 tex and a low pile height could be a good compromise to obtain woolen hand-made carpet with a good resilience and an important useful life. [Extracted from the article]

The study of loading-unloading cycle of hair showed that hair in water can resist to fatigue more than dry hair (65% RH). Hair fibers are also subjected to unfixed number of cycles of fatigue until the fiber was broken in order to understand the hysteresis behavior of these fibers in the two mentioned environmental situations. Results and discussions Hair mechanical behavior Tensile properties at 65% RH The mechanical behavior of hair fiber at 21°C and 65% RH is shown in Figure 1. Hair fiber consists of hair bulb, hair follicle and hair shafts. [Extracted from the article]