In this study, 32 different electro-conductive fabrics and seven different non-conductive fabrics were taken for an analysis of their electromagnetic shielding ability, electrical resistivity and air permeability. According to the present state of development of electromagnetic shielding textile structures, a diverse set of samples was selected, including stainless steel, copper, silver, aluminum, carbon and polypyrrole as a conductive component. The ASTM D4935 coaxial transmission line method was used to study the electromagnetic shielding and the ASTM D257 ring electrode method was used to evaluate the surface and volume electrical resistivity of all the samples. Air permeability was considered as an additional important parameter for the production of electromagnetic radiation protective fabrics designed for technical or clothing applications. It was confirmed that textile structures made of conventional textile fibers are transparent to an electromagnetic field. The electromagnetic shielding effectiveness of non-conductive samples is less than 0.2 dB regardless of material composition. On the other hand, the electromagnetic shielding effectiveness of electro-conductive samples containing different content and types of conductive component ranges from 1 to 79 dB at the high-frequency range, whereas the woven sample containing 75 wt% of staple metal fiber provides excellent shielding ability together with high air permeability. It was confirmed that, in particular, the surface resistivity can be used to predict the electromagnetic shielding ability of fabric samples due to a strong inverse relationship between these two parameters.

Electromagnetic (EM) radiation is everywhere in this world and galaxy in different forms and levels. In some cases, human beings need to protect themselves from electromagnetic radiations and the same thing is also recommended for electronic devices as well. Lots of studies are there on the shielding of electromagnetic radiation interference using metals, polymers, and minerals. For protecting the human being, textile structures are playing the main role. In the textile material structure itself many types are there; each one is having its unique geometrical shape and design. In this work, the copper/nickel-coated ultrathin nonwoven fabric is prepared like a strip. The 3, 6, and 9 mm thick strips are prepared and laid at different gaps, angles, and layered to study the effect of factors on EM shielding effectiveness as per ASTM D4935-10 standard. The design of experiment has been done to analyze the three factors and three levels of the strip properties having an influence on electromagnetic shielding results. From the findings of the design of experiment (DoE) screening design, the factors are the thickness of the strips, the gap between the strips, and the strips laid angle having a statistically significant effect on electromagnetic shielding effectiveness.

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Electromagnetically shielding textile materials, especially in professional or ordinary clothing, are used to protect an implanted pacemaker in the body. Alternatively, traditional textiles are known for their non-conductivity and transparency to an electromagnetic field. The main goal of this work was to determine whether the high moisture content (sweat) of the traditional textile structure significantly affects the resulting ability of the material to shield the electromagnetic field. Specifically, whether sufficient wetting of the traditional textile material can increase its electrical conductivity to match the electrically conductive textiles determined for shielding of the electromagnetic field. In this study, cotton and polyester knitted fabric samples were used, and two liquid medias were applied to the samples to simulate human sweating. The experiment was designed to analyse the factors that have a significant effect on the shielding effectiveness that was measured according to ASTM D4935. The following factors have a significant effect on the electromagnetic shielding effectiveness of moisturised fabric: squeezing pressure, drying time and type of liquid media. Additionally, the increase of electromagnetic shielding was up to 1 dB at 1.5 GHz frequency at the highest level of artificial sweat moisturised sample.

Abstract. This study was focussed to investigate the effect of fluorocarbon, hydrocarbon and hybrid fluorocarbon on the mechanical properties and moisture regain of jute fiber reinforced composites. A significant difference in moisture regain values of treated and untreated reinforcement samples was observed at a concentration of 40 g/l. The composite made from treated reinforcement regained very low moisture content and exhibited improved mechanical properties (tensile and flexural strength). Being dual nature (hydrophilic and hydrophobic groups) of Hybrid fluorocarbon, the treated jute fibers and corresponding composites showed better properties as compared to other two chemicals due to better interface.