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The change rules of the shielding effectiveness (SE) of the sleeve has not been clarified, which leads to the lack of the basis for the design, manufacture and evaluation of the electromagnetic shielding (EMS) clothing.

According to a simplified analysis model, a series of sleeve samples with different fabrics and styles are designed and manufactured. The SE of the sleeve is tested with the proposed special test method in a semi-anechoic chamber to analyze the influence of different factors on the SE of the sleeve.

The SE is greatly reduced about 60–90% after the fabric is manufactured into the sleeve. The larger the sleeve length is, the higher the peak value of the SE is. When the sleeve length is low, the SE value is easy to appear negative. As the cuff circumference increases, the SE of the sleeve will change with the frequency band. The influence of the cuff style on the SE of the sleeve mainly depends on the cuff width and style. The larger the cuff width is, the lower the overall SE of the sleeve is. The more wrinkles there are at the cuff, the better the SE of the sleeve is.

Our results provide a reference for the design, production and evaluation of the sleeve and the whole EMS clothing.

Stainless-steel electromagnetic shielding (EMS) fabrics are widely applied as protective materials against electromagnetic interference (EMI). However, these fabrics primarily shield electromagnetic waves through reflection, which can lead to the formation of resonance effects that severely compromise their protective capabilities and potentially cause secondary electromagnetic pollution in the external environment.

In this paper, carbon nanotube fibers are added via spacing method to replace some stainless-steel fibers to impart absorbing properties to stainless-steel EMS fabric. The shielding effectiveness (SE) of the EMS fabrics across various polarization directions is analyzed. Additionally, a spacing arrangement for the carbon nanotube fibers is designed. The EMS fabric with carbon nanotube fibers is manufactured using a semi-automatic sample loom, and its SE is tested using a small window method test box in both vertical and horizontal polarization directions.

According to the experimental data and electromagnetic theory analysis, it is determined that when the spacing between the carbon nanotube fibers is less than a specific distance, the SE of the stainless-steel EMS fabric significantly improves. The fabric exhibits stable absorbing properties within the tested frequency range, effectively addressing the issue of secondary damage that arises from relying solely on reflective shielding. Conversely, as the spacing between the carbon nanotube fibers exceeds this distance, the SE diminishes. Notably, the SE in the vertical polarization direction is substantially higher than that in the horizontal polarization direction at the same frequency.

This study provides a new path for the development of high-performance EMS fabrics with good wave-absorption characteristics and SE.

Nylon 6 filaments have weak light and heat resistance in terms of stability, which restrict its application in engineering field. The purpose of this paper is to prepare a new photo-stabilization functional nanocomposite inks by using graphene nanosheet as UV light-resisting functional materials incorporated with polyurethane.

Sunlight-resisting functional nylon filaments were produced by the continuous solution dip coating technology, through which the functional inks was coated on the surface of nylon 6 filament. The surface morphology of the coated filaments was characterized by scanning electron microscopy and the graphene/polyurethane nanocomposite inks as the coating agent was confirmed and well dispersed on the fiber’s surface.

Under UV exposure, the strength loss rate of the graphene-modified nylon filaments was less than 50 percent, while that of the control nylon filament was over 85 percent, which indicated that graphene remarkably enhanced the light-resistant property of nylon. Besides, graphene/polyurethane-coated Nylon 6 filaments exhibited reasonable electrical properties and the electrical conductivity could reach 10–4 S/cm.

Graphene inks was first proposed as the UV photo-stabilization in this paper.

This study aims to fabricate a multifunctional electromagnetic interference (EMI) shielding composite fabric with simultaneous high-efficiency photothermal conversion and Joule heating performances.

A multifunctional polypyrrole (PPy) hydrogel/multiwalled carbon nanotube (MWCNT)/cotton EMI shielding composite fabric (hereafter denoted as PHMC) was prepared by loading MWCNT onto tannin-treated cotton fabric, followed by in situ crosslinking-polymerization to synthesize three-dimensional (3D) conductive networked PPy hydrogel on the surface of MWCNT-coated cotton fabric.

Benefiting from the unique interconnected 3D networked conductive structure of PPy hydrogel, the obtained PHMC exhibited a high EMI-shielding effectiveness vale of 48 dB (the absorbing electromagnetic wave accounted for 84%) within a large frequency range (8.2–12.4 GHz). Moreover, the temperature of the laminated fabric reached 54°C within 900 s under 15 V, and it required more than 100 s to return to room temperature (28.7°C). When the light intensity was adjusted to 150 mW/cm², the PHMC temperature was about 38.2°C after lighting for 900 s, indicating high-efficiency electro-photothermal effect function.

This paper provides a novel strategy for designing a type of multifunctional EMI shielding composite fabric with great promise for wearable smart garments, EMI shielding and personal heating applications.

With the popularization of electronic products, the electromagnetic radiation pollution has been the fourth largest pollution after water, air and noise pollution. Therefore, electromagnetic shielding property of textiles is attracting more attention. In this paper, the properties of electromagnetic shielding yarns and fabrics were studied.

Ten kinds of yarn, stainless steel short fiber and polyester blend yarn with three different blending ratios T/S 90/10, T/S 80/20 and T/S 70/30, stainless steel short fiber, polyester and cotton blend yarn with blending ratio C/T/S 35/35/30, core-spun yarn with one 30 um stainless steel filament C/T28tex/S(30 um), core-spun yarn with two 15 um stainless steel filaments (C/T28tex/S(15 um)/S(15 um)), twin-core-spun yarn with one 30 um stainless steel filament and one 50D spandex filament C/T28tex/S(30 um)/SP(50D), sirofil wrapped yarn with one 30 um stainless steel filament feeding from left S(30 um)+C/T28tex, sirofil wrapped yarn with one 30 um stainless steel filament feeding from right C/T28tex+S(30 um), sirofil wrapped yarn with two 15 um stainless steel filaments feeding from two sides S(15 um)+C/T28tex+ S(15 um), were spun. The qualities of spun yarns were measured. Then, for analyzing the electromagnetic shielding properties of fabrics made of different spun yarns, 20 kinds of fabrics were woven.

The tested results show that comparing to the T/S 80/20 blend yarn, the resistivity of composite yarns with the same ratio of the stainless steel filament is smaller. The possible reason is that comparing to the stainless steel short fiber, the conductivity of stainless steel filament is better because of the continuous distribution of stainless steel in the filament. Comparing with the core-spun yarn, the conductivity of the sirofil wrapped yarn is a little better. Comparing to the fabric woven by the blend yarn, the electromagnetic shielding of the fabric woven by the composite yarn is better, and comparing to the fabric woven by the core-spun yarn, the electromagnetic shielding of the fabric woven by the sirofil yarn is a little better. The possible reason is that the conduction network can be produced by the stainless steel filament wrapped on the staple fiber yarn surface in the fabric, and the electromagnetic wave can be transmitted in the network.

In this paper, the properties of electromagnetic shielding yarns and fabrics were studied. Ten kinds of yarn, including three stainless steel short fiber and polyester blend yarns, one stainless steel short fiber, polyester and cotton blend yarn, two core-spun yarns, one twin-core-spun yarn, three sirofil wrapped yarn, were spun. Then, for analyzing the electromagnetic shielding properties of fabrics made of different spun yarns, 20 kinds of fabrics were woven. The effects of fabric warp and weft densities, fabric structures, yarn kinds, yarn distributions in the fabric on electromagnetic shielding were analyzed.

Nanoscale copper (Cu) films were deposited onto the surface of polyester fabrics with different structures using radio frequency magnetron sputter coating system at room temperature. The paper aims to discuss these issues.

Scanning electron microscopy (SEM) and field emission scanning electron microscopy (FE-SEM) were used to observe the surface morphology of substrates and the structures of the deposited copper particles, respectively. The capillary flow pore instrument was used to measure pore sizes distribution of polyester substrates.

The experimental results revealed that the fabric structures had a more significant role on the conductivity and electromagnetic shielding effectiveness of samples. The porosity had more apparent effect on ultraviolet transmittance of samples.

The results have some theory values on the development of functional textiles.

In this article, the authors intended to analyze the shielding properties of a fabric frequency selective surface (FSS) structure to the basis of substrate fabric properties. For this purpose, the effect of the properties and structural parameters of the substrate fabric layer were analyzed on the shielding properties of the developed FSS.

The experimental and theoretical evaluations were done at the frequency band of 1,805–1,880 MHz and computer simulation technology (CST) was used in modeling. In experiments were developed the FSS structures by different fabrics as the substrate layers and the copper as the patch cells. The shielding properties of these samples were measured experimentally by the developed setup.

Confirming resonant frequencies, transmission coefficients, and the bandwidths results obtained from modeling and experiments show that the thickness, weight and interweaving structure parameters were affect the porosity of the substrate fabric. Porosity of the fabric moves the resonant frequency due to the changing of the dielectric properties of the fabric. Therefore, shielding properties of the FSS structure were affected by these parameters as the important characteristics of the substrate fabric. In addition, shielding properties of the samples (resonant frequencies and transmission coefficients) in different incident angles are not same in two modes of transverse electric and transfer magnetic.

The experimental results suggest that the introduced flexible FSS structures are suitable for shielding applications in the proposed frequency band.

The purpose of this paper is to explore the influence of hole on shielding effectiveness (SE) of electromagnetic shielding (EMS) fabric under incident polarization wave, and to propose a “Key Size” theory to explain the influence mechanism.

“Key Size” parameters describing hole shape are established, and a number of representative samples with rectangular and oval holes are made. SE of the samples are tested by waveguide testing system. Influence of the hole on the SE of the samples is analyzed according to vertical or horizontal maximum size and polarization wave direction. Finally, the “Key Size theory” and “Secondary Size theory” are proposed to explain the influencing mechanism.

The hole influences on the SE are related to the vertical and the horizontal maximum size of the holes and the direction of the polarization wave. As the direction of the polarization wave is vertical (or horizontal), greater maximum size results in lower SE. As the maximum size is constant, greater maximum size causes lower SE. As the maximum size reaches to a certain value, a dividing point of the SE occurs. As the direction of the polarization wave is consistent with the direction of the maximum size, same hole area results in same SE.

The explored influences and mechanism provide an important guiding reference for the hole design of the EMS fabric, and can be applied to the holes design of the EMS garment, composite materials, and tents.

The purpose of this paper is to propose a new indicator-gray porosity that can objectively evaluate real porosities of electromagnetic shielding (EMS) fabric based on computer image analysis, which aims to address current porosity evaluation by tightness.

A method for the fabric image acquisition is determined and a gray digital model is established. The porosity membership region of true porosity is judged according to the total gray wave. A bi-directional judgment method based on horizontal and vertical single gray waves is proposed to automatically identify the gray porosity in the porosity membership region. After experiments, the differences between the gray porosity indicator and the tightness indicator are analyzed, the influence of the gray porosity on the shielding effectiveness (SE) is discussed, and the advantages of the gray porosity indicator are detailed.

Results show that the proposed indicator can accurately represent the real porosity size of the EMS fabric without pre-acquiring the structure parameters of the fabric, which provides a reference for the study of the electromagnetic characteristic of the EMS fabric.

The gray porosity presented in this paper is a new method to objectively evaluate real porosities of the EMS fabric, and can be applied to the research and evaluation of the electromagnetic characteristic for the EMS fabric.

In this research project, electrical conductive yarns were knitted together with 100 per cent cotton yarns to create knitted fabrics that would be used as electromagnetic (EM) shielding materials. The paper aims to discuss these issues.

1×1 plain fabrics knitted on double-bed hand knitting machines of five and seven gauges. Several strands of the cotton yarns were used together in order to knit samples with good handling properties. The electrical conductive yarn has six plies and each ply has 29 filaments with Naño-coating of silver and having an electrical resistance of 4 Ohms per 100 mm and a count of 96 Tex. The knitted fabrics have similar texture but vary in term of specific weight, fabric density, loop length, Tex, tightness factor, thickness and electrical conductivity. These variations affected the properties of the fabrics, determining factors of a good shielding or not. A special designed Faraday cage was built to measure the EMSE of each knitted fabrics. The EM waves were sent through the signal generator at different frequencies as from 400 to 1,100 MHz and with three different power inputs of 10, 20 and 30 dBm. EMSE measurements were also carried out after the knitted samples were rotated clockwise.

Good EMSE shielding results were achieved with the knitted samples, however in this study it was found that different knitted fabrics shielded better at specific frequencies and power inputs.

Knitted fabrics can be used to develop comfortable garments that can be used to shield EM waves and protect the wearer.

The choice of using the conductive yarns is exclusive. In addition the EMSE were measured with fabrics knitted in the same structure but on different knitting machine gauge. Three different power inputs were considered and EMSE measurements were taken using frequencies as from 400 to 1,100 MHz. A new method for measuring the electrical resistance on the knitted fabrics and the method used for measuring the EMSE for each knitted fabric were considered.