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Composites were developed by reinforcing available non-woven Lyocell and viscose in acrylated epoxidized soybean oil (AESO). Compression molding was used to make composites with 40–60 wt% fiber content. The fiber content comprises only Lyocell or viscose fiber, or mixture of these fibers in known ratio. Hybrid composites were made by a mixture of both the fibers in known ratio and it affects the properties. The effect of hybridization was evident in most tests which gives us an opportunity to tailor the properties according to requirement. Lyocell fiber reinforced composites with 60 wt% fiber content had a tensile strength and modulus of about 135 MPa and 17 GPa, respectively. Dynamic mechanical analysis showed that the Lyocell fiber reinforced composites had good viscoelastic properties. The viscose fiber reinforced composites had the high percentage elongation and also showed relatively good impact strength and flexural modulus. Good fiber-matrix adhesion reflected in mechanical properties. SEM images were made to see the fiber-matrix compatibility. [ABSTRACT FROM AUTHOR]

The functionalization of textile fibers with intrinsically conductive polymers has become a prominent research area throughout the world. A number of coating techniques have already been utilized and optimized to get the uniform layers of conductive polymers on the surface of different substrates. In our previous study, we produced poly(3,4-ethylenedioxythiophene) (PEDOT)-coated conductive fibers by employing oxidative chemical vapor deposition (oCVD) technique. This paper describes the effects of pre-treatment steps, such as surface treatment of textile fibers with organic solvents, drying of oxidant-enriched fibers at variable temperatures and time, and oxidant type on the electrical, mechanical, and thermal properties of PEDOT-coated conductive fibers. Two well-known oxidants, ferric(III)chloride and ferric(III)p-toluenesulfonate (Fe pTS), were studied, and then their results were compared. In order to verify the PEDOT-coated layer and, to some extent, its impregnation inside the viscose yarns, a morphological study was carried out by using the attenuated total reflectance Fourier transform infrared spectroscopic imaging technique and computed tomography scanning across the obtained conductive fibers. Differential scanning calorimetric and thermogravimetric analysis were utilized to investigate the thermal properties and the contents of PEDOT in PEDOT-coated fibers. The mechanical properties of conductive fibers were evaluated by tensile strength testing of produced fibers. Effects of all of these pre-treatment steps on electrical properties were analyzed with Kiethly picoammeter. This study cannot only be exploited to improve the properties of conductive fibers but also to optimize the oCVD process for the production of conductive textile fibers by coating with different conjugated polymers. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Textile fibers and yarns of high conductivity, and their integration into wearable textiles for different electronic applications, have become an important research field for many research groups throughout the world. We have produced novel electrically conductive textile yarns by vapor-phase polymerization (VPP) of a conjugated polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), on the surface of commercially available textile yarns (viscose). In this article, we have presented a novel setup for electrical resistance measurements, which can be used not only for fibrous structures but also for woven structures of specific dimensions. We have reported a two-point resistance-measuring method using an already manufactured setup and also a comparison with the conventionally used method (so-called crocodile clip method). We found that the electrical properties of PEDOT-coated viscose fibers strongly depend on the concentration of oxidant (FeCl3) and the doping (oxidation) process of PEDOT. To evaluate the results, we used mass specific resistance values of PEDOT-coated viscose yarns instead of normal surface resistance values. The voltage-current ( V- I) characteristics support the ohmic behavior of coated fibers to some extent. Monitoring of the charging effect of the flow of current through conductive fibers for prolonged periods of time showed that conductivity remains constant. The change in electrical resistance values with increase in the length of coated fibers was also reported. The resistance-measuring setup employed could also be used for continuous measurement of resistance in the production of conductive fibers, as well as for four-point resistance measurement. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Production of high performance conductive textile yarn fibers for different electronic applications has become a prominent area of many research groups throughout the world. We have used oxidative chemical vapor deposition (OCVD) technique to coat flexible and high strength polyester yarns with conjugated polymer, poly(3,4-ethylenedioxythiophene) (PEDOT) in presence of ferric (III) chloride (FeCl3) oxidant. OCVD is an efficient solvent free technique used to get uniform, thin, and highly conductive polymer layers on different substrates. In this paper, PEDOT-coated polyester (PET) yarns were prepared under specific reaction conditions, and the electrical, mechanical and thermal properties were compared to previously studied PEDOT-coated viscose yarns. Scanning electron microscopy (SEM) and FT-IR analysis revealed that polymerization of PEDOT on the surface of the polyester yarns has been taken place successfully and structural analysis showed that PEDOT has strong interactions with viscose yarns as compared to PET yarns. The voltage-current ( V- I) characteristics showed that PET yarns are more conductive than PEDOT-coated viscose yarns. The variation in the conductivity of PEDOT-coated yarns and the heat generation properties during the flow of current through coated yarns for longer period of time, was studied by time-current ( t- I) characteristics. Thermogravimeteric analysis (TGA) was employed to investigate the thermal properties and the amount of PEDOT in PEDOT-coated PET yarns compared to PEDOT-coated viscose. The effect of PEDOT coating and ferric (III) chloride concentration on the mechanical properties of coated yarns was evaluated by tensile testing. The obtained PEDOT-coated conductive polyester yarns could be used in smart clothing for medical and military applications. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Escalations of living standards are integrally bound with energy consumption. Sustainable supply demands have become difficult to afford in conventional mode of use. Smart approach is inevitable and demands sensitive response to jump out of the scenario in a holistic approach and save our resources for further betterment and civic civilization. Corporate practices on energy management have developed smart benchmarks and earned fortune. Current study is to extract a holistic approach and facilitate learning upon lessons for integrated benefits of developing countries like Pakistan in particular and the world in general by managing energy crisis. [ABSTRACT FROM AUTHOR]

The development of electrically conductive fibers, exhibiting higher mechanical properties and their integration in smart and interactive textiles, has become a prominent research area throughout the world. Smart textiles have increasingly been used in medical, sports and military applications. In other words, we can say, smart textiles are going to shape our future. This paper describes our ongoing research in which, we have produced relatively highly conductive fibers by coating commercially available textile fibers (viscose, polyester) with conductive polymer, poly(3,4-ethylenedioxythiophene) (PEDOT). A novel coating technique, called oxidative chemical vapor deposition (OCVD), was used for this purpose. Different testing and characterization techniques were then employed to investigate electrical, mechanical, thermal, and surface properties of PEDOT coated fibers. The surface modification of electrically conductive textile fibers with silicone resins is also discussed and an analysis is given to show how silicone coating enhances the mechanical as well as hydrophobic properties of coated textile fibers. The obtained PEDOT coated textile fibers showed good electrical as well as mechanical properties. From this research, we can easily select the most appropriate type of fiber according to the specific electronic application, exhibiting the required end-used properties. These conductive fibers could also be used as substrates for heat generation devices, such as solar cells, and organic fuel cells. [ABSTRACT FROM AUTHOR]

Like skeletal muscles having a fibrous structure, conducting polymers can actuate upon electrical stimulation and can be shaped into fibers. Through textile assembly strategies of such fibers, complex actuating architectures are possible. However, state‐of‐the‐art strategies using short pieces of yarn, which compel manual integration, are not fully taking advantage of textiles. To manufacture actuating textiles that best exploit textile properties like softness and pliability, and to enable production upscaling, a production of continuous, actuating fibers is presented here. These fibers are produced from commercial polyamide 6/6 filaments by first continuously dip‐coating in a modified commercial poly(3,4−ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) dispersion before the electropolymerization of polypyrrole (PPy), where the fibers are withdrawn continuously through an electrolyte solution containing the pyrrole monomer. By employing a cyclic dip‐coating with individual viscosity, drying temperature, and withdrawal speed for each layer, and by adjusting the tension, speed, and applied potential of the electropolymerization, their isotonic strain is enhanced threefold. Their specific tension, at 400 µN tex−1, reaches slightly higher than human skeletal muscle fibers. Furthermore, these continuous actuating fibers produced on the meter are processable in an industrial knitting machine. This study anchors the development of textile muscle fibers for future textile muscles. [ABSTRACT FROM AUTHOR]

Background: Renewable materials made using environmentally friendly processes are in high demand as a solution to reduce the pollution created by the fashion industry. In recent years, there has been a growing trend in research on renewable materials focused on bio-based materials derived from fungi., Results: Recently, fungal cell wall material of a chitosan producing fungus has been wet spun to monofilaments. This paper presents a modification for the fungal monofilament spinning process, by the development of a benign method, dry gel spinning, to produce continuous monofilaments and twisted multifilament yarns, from fungal cell wall, that can be used in textile applications. The fungal biomass of Rhizopus delemar, grown using bread waste as a substrate, was subjected to alkali treatment with a dilute sodium hydroxide solution to isolate alkali-insoluble material (AIM), which mainly consists of the fungal cell wall. The treatment of AIM with dilute lactic acid resulted in hydrogel formation. The morphology of the hydrogels was pH dependent, and they exhibited shear thinning viscoelastic behavior. Dry gel spinning of the fungal hydrogels was first conducted using a simple lab-scale syringe pump to inject the hydrogels through a needle to form a monofilament, which was directly placed on a rotating receiver and left to dry at room temperature. The resulting monofilament was used to make twisted multifilament yarns. The process was then improved by incorporating a heated chamber for the quicker drying of the monofilaments (at 30⁰C). Finally, the spinning process was scaled up using a twin-screw microcompounder instead of the syringe pump. The monofilaments were several meters long and reached a tensile strength of 63 MPa with a % elongation at break of 14. When spinning was performed in the heated chamber, the tensile strength increased to 80 MPa and further increased to 103 MPa when a micro-compounder was used for spinning., Conclusion: The developed dry gel spinning method shows promising results in scalability and demonstrates the potential for renewable material production using fungi. This novel approach produces materials with mechanical properties comparable to those of conventional textile fibers., (© 2024. The Author(s).)

The study explores the synergy of biobased polymers and hydrogels for water purification. Polymer nanomaterial's, synthesized by combining acrylamide copolymer with maleic anhydride, were integrated into sodium alginate biopolymer using an eco-friendly approach. Crosslinking agents, calcium chloride and glutaraladehyde, facilitated seamless integration, ensuring non-toxicity, high adsorption performance, and controlled capacity. This innovative combination presents a promising solution for clean and healthy water supplies, addressing the critical need for sustainable environmental practices in water purification. In addition, the polymer sodium alginate hydrogel (MAH@AA-P/SA/H) underwent characterization via the use of several analytical procedures, such as FTIR, XPS, SEM, EDX and XRD. Adsorption studies were conducted on metals and dyes in water, and pollutant removal methods were explored. We investigated several variables (such as pH, starting concentration, duration, and absorbent quantity) affect a material's capacity to be adsorbed. Moreover, the maximum adsorption towards Cu 2+ is 754 mg/g while for Cr 6+ metal ions are 738 mg/g, while the adsorption towards Congo Red and Methylene Blue dye are 685 mg/g and 653 mg/g correspondingly, within 240 min. Adsorption results were further analyzed using kinetic and isothermal models, which showed that MAH@AA-P/SA/H adsorption is governed by a chemisorption process. Hence, the polymer prepared from sodium alginate hydrogel (MAH@AA-P/SA/H) has remarkable properties as a versatile material for the significantly elimination of harmful contaminants from dirty water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this paper, we analyze the performance of an intelligent reflecting surface (IRS)-aided terahertz (THz) wireless communication system with pointing errors. Specifically, we derive closed-form analytical expressions for the upper bounded ergodic capacity and approximate expression of the outage probability. We adopt an α-μ fading channel model for our analysis that is experimentally demonstrated to be a good fit for THz small-scale fading statistics, especially in indoor communication scenarios. In the proposed analysis, the statistical distribution of the α-μ fading channel is used to derive analytical expressions for the ergodic capacity and outage probability. Our proposed analysis considers not only the IRS reflected channels, but also the direct channel between the communication nodes. The results of the derived analytical expressions are validated through Monte Carlo simulations. Through simulations, it has been noticed that pointing errors degrade the performance of the IRS-assisted THz wireless communication system which can be compensated by deploying an IRS having a large number of reflecting elements.

Ni-Mo 2 C nano catalysts dispersed on N-doped carbon flowers: a composite with nitrogen-containing carbon flowers carrying nickel-modified molybdenum carbide exhibits enhanced HER catalytic activity in alkaline electrolyte.

Electro-organic synthesis has attracted a lot of attention in pharmaceutical science, medicinal chemistry, and future industrial applications in energy storage and conversion. To date, there has not been a detailed review on electro-organic synthesis with the strategy of heterogeneous catalysis. In this review, the most recent advances in synthesizing value-added chemicals by heterogeneous catalysis are summarized. An overview of electrocatalytic oxidation and reduction processes as well as paired electrocatalysis is provided, and the anodic oxidation of alcohols (monohydric and polyhydric), aldehydes, and amines are discussed. This review also provides in-depth insight into the cathodic reduction of carboxylates, carbon dioxide, CC, C≡C, and reductive coupling reactions. Moreover, the electrocatalytic paired electro-synthesis methods, including parallel paired, sequential divergent paired, and convergent paired electrolysis, are summarized. Additionally, the strategies developed to achieve high electrosynthesis efficiency and the associated challenges are also addressed. It is believed that electro-organic synthesis is a promising direction of organic electrochemistry, offering numerous opportunities to develop new organic reaction methods., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

An experimental study of high-density polyethylene (HDPE) composites filled with talc (0-15 wt.%) was carried out to investigate the rheological properties. The apparent melt viscosity, melt density, and die-swell ratio ( B ) of the composites were measured at constant shear stress and constant shear rate by using a melt flow indexer and capillary rheometer. The experimental conditions were set to a temperature range from 190 to 220 °C for both apparatuses whereas a load range from 5 to 12.16 kg was selected for melt flow indexer and shear rate range from 1 to 10000 s -1 for capillary rheometer. The initial study showed that the talc particulates did not influence the melt viscosity compared with the neat HDPE but decreased the elasticity of the polymer system. The HDPE/talc systems obeyed power-law model in shear stress-shear rate variations and were shear thinning, meanwhile, the die-swell increased with an increased wall shear rate and shear stress. The melt density of the composites increased linearly with an increase of the filler weight fraction and decreased with the increase of the testing temperature. The talc-HDPE composites showed compressible in the molten state., (© 2020 The Author(s).)