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The present study aimed to develop wearable, electrically conductive hygienic electrodes and their use for Transcutaneous Electrical Nerve Stimulation (TENS) application. The development of electrodes was done in two stages. Firstly, the dispersion of conductive activated carbon particles was done into flexible elastomer followed by its silver electroplating. The Orthogonal Array Testing (OATS) technique was used to optimize the silver-plating recipe. The Fourier transform infrared spectroscopy (FTIR) analysis confirmed the impact of activated carbon by increase in intensity of stretching bands. To improve electrode properties in response to various human body movements, resistivity changes due to stretching and repeated extension were tested on conductive elastomers. Increasing the extension degree allowed a very minute change in electrical resistivity. Therefore, the resistivity can be considered almost constant within the 0-60 % stretch range. While, a notable increase in electrical resistivity was observed after 70 % of stretch. However, the resistivity of elastomers remained stable even after repetitive extension (for over 100 cycles). Conversely, no significant change in resistivity was observed over time when subjected to a constant current. Furthermore, to minimize the effect of skin electrode resistivity during electrotherapy, the range of different pressure was applied over the surface of electrodes. Minimum value of resistivity about 1 Ω.mm was obtained at 6 N/cm2 of applied pressure. Additionally, hygienic properties, such as antiviral, antibacterial and antifungal were examined using different pathogens to assess the impact of the deposited silver particles. In the end, the durability of electrodes against washing and rubbing was confirmed. The potential applications of prepared electrodes are in the field of electrostimulation and electrotherapy etc. [ABSTRACT FROM AUTHOR]

Polyester is a popular class of material used in material engineering. With its 0.4% moisture regain, polyethylene terephthalate (PET) is classified as highly hydrophobic, which originates from its lack of polar groups on its backbone. This study used a parallel-plate nonthermal plasma dielectric barrier discharge system operating at medium pressure in dry air and nitrogen (N2) to alter the surface properties of PET fabrics to increase their hydrophilic capabilities. Water contact angle, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS) were utilized to analyze any effect from the plasma treatment. The wettability analysis revealed a reduction in the contact angle of more than 80% within 5 min for both discharges. Scanning electron microscopy analysis showed no microscopic damage to the fiber structure, guaranteeing that the fabrics’ structural integrity was preserved after treatment. AFM analysis showed an increase in the nanometer roughness, which was considered beneficial because it increased the total surface area, further increasing the hydrophilic capacity. XPS analysis revealed a sharp increase in the presence of polar functional groups, indicating that the induced surface changes are mostly chemical in nature. Comparing that of untreated fabrics to treated fabrics, a Increase in water absorption capacity was observed for air-treated and N2-treated fabrics, when these fabrics were used immediately after plasma exposure.

Bacterial cellulose (BC) presents significant promise as a biomaterial, boasting unique qualities such as exceptional cellulose purity, robust mechanical strength, heightened crystalline structure, and biodegradability. Several studies have highlighted specific effects, such as the impact of dehydration/rehydration on BC tensile strength, the influence of polymer treatment methods on mechanical properties, the correlation between microorganism type, drying method, and Young's modulus value, and the relationship between culture medium composition, pH, and crystallinity. Drying methods are crucial to the structure, performance, and application of BC films. Research findings indicate that the method used for drying can influence the mechanical properties of BC films, including parameters such as tensile strength, Young's modulus, and water absorption capacity, as well as the micromorphology, crystallinity, and thermal characteristics of the material. Their versatility makes them potential biomaterials applicable in various fields, including thermal and acoustic insulation, owing to their distinct thermal and mechanical attributes. This review delves into the thermal and mechanical behavior of bacterial cellulose aerogels, which are profoundly impacted by their drying mechanism. [ABSTRACT FROM AUTHOR]

In this work, we developed a novel harp structure that collects water directly from fog in comparison with conventional Raschel mesh. Polyethylene (PE) monofilament was used as a collector's element in the harp. The Raschel mesh in its particular design is quite anisotropic, shows elastic behavior breadth-wise while no stiffness is exhibited in transverse direction. A comparison of fog collection yield for the harp signifies that fog harvesting rate is four times higher than Raschel mesh, suggesting some alterations in monofilament diameter and collector element. Therefore, harp technology with cylindrical monofilaments can be deployed commercially to increase the efficiency of fog collectors, where mass and velocity of fog are inappropriate for Raschel mesh. In addition, silane-coated harp showed that surface hydrophobicity further enhances fog collection efficiency. The fog collector element (FCE) after silane coating significantly enhanced fog water collection yield. Samples were characterized by high resolution scanning electron microscope (HR-SEM), energy-dispersive x-ray (EDX) and atomic force microscope (AFM). Hydrophobicity was analyzed by static water contact angle and water collection yield. [ABSTRACT FROM AUTHOR]

More than a third of microplastics in surface waters are formed by microplastics released from textile products containing textile fibers (fibrous microplastics). A large amount of fibrous microplastics enters the environment during textile production and the first few washing cycles. Mechanical, thermal, chemical, and biological damage to textiles causes the generation of fibrous microplastics. Textile manufacturers, dyers and finishers, garment producers, distributors, or consumers contribute to this process. During the construction of textiles, multiple issues need to be addressed simultaneously. They are related to the optimization of technological processes and the construction and functionalization of fiber structures, considering ecological requirements, including suppressing the formation of fibrous microplastics. This research is focused on the specification of reasons for the generation of fibrous microplastics during textile production. The influence of the structure of fibers, abrasive deformations, and surface structure of fabrics on the generation of fibrous microplastics is discussed. The release of fibrous microplastics during washing is mentioned as well. [ABSTRACT FROM AUTHOR]