scholarly journals Electromagnetic Interference Shielding of Metal Coated Ultrathin Nonwoven Fabrics and Their Factorial Design

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 484
Author(s):  
Sundaramoorthy Palanisamy ◽  
Veronika Tunakova ◽  
Shi Hu ◽  
Tao Yang ◽  
Dana Kremenakova ◽  
...  
Keyword(s):  
Design Of Experiment ◽  
Electromagnetic Interference ◽  
Nonwoven Fabric ◽  
Electromagnetic Shielding ◽  
Material Structure ◽  
Main Role ◽  
Geometrical Shape ◽  
Human Beings ◽  
Shielding Effectiveness ◽  
Screening Design

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.

scholarly journals Conducting Polymeric Composites Based on Intrinsically Conducting Polymers as Electromagnetic Interference Shielding/Microwave Absorbing Materials—A Review

2021 ◽  
Vol 5 (7) ◽  
pp. 173
Author(s):  
Bluma Guenther Soares ◽  
Guilherme M. O. Barra ◽  
Tamara Indrusiak
Keyword(s):  
Conducting Polymers ◽  
Electromagnetic Interference ◽  
Electromagnetic Shielding ◽  
Human Beings ◽  
Shielding Effectiveness ◽  
Electromagnetic Interference Shielding ◽  
Preparation Methods ◽  
Microwave Absorbing Materials ◽  
Microwave Absorbing ◽  
Intrinsically Conducting Polymers

The development of sophisticated telecommunication equipment and other electro-electronic devices resulted in a kind of electromagnetic pollution that affects the performance of other equipment as well as the health of human beings. Intrinsically conducting polymers (ICP), mainly polyaniline and polypyrrole, have been considered as promising candidates for applications in efficient electromagnetic interference shielding (EMI) due to their ease of preparation, light weight, good conductivity and corrosion resistance. One of the important advantages of these materials is the capability to interact with the EM radiation through both absorption and reflection mechanisms thus enlarging the field of application. In this context, this review article describes a recent overview of the existing methods to produce intrinsically conducting polymers and their blends for electromagnetic shielding application. Additionally, it highlights the relationship between preparation methods reported in the literature with the structure and properties, such as electrical conductivity, electromagnetic shielding effectiveness (EMI SE), complex permittivity and permeability of these materials. Furthermore, a brief theory related to the electromagnetic mechanism and techniques for measuring the microwave absorbing properties are also discussed.

Realization of electromagnetic shielding performance for polyimide-matrix composite by self-metallization

2021 ◽  
pp. 002199832110316
Author(s):  
Jiayang Zhang ◽  
Hongjiang Ni ◽  
Ming Gong ◽  
Jun Li ◽  
Daijun Zhang ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Matrix Composite ◽  
Electromagnetic Interference ◽  
Interfacial Strength ◽  
Amic Acid ◽  
Thermal Reduction ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Heat Condition ◽  
Electromagnetic Interference Shielding Effectiveness

Electromagnetic shielding performance has been achieved for a polyimide (PI)-matrix composite by the strategy of self-metallization of its thermosetting PI matrix. Self-metallization of the thermosetting PI was realized by silver ion/poly(amic acid) (PAA) precursor ion exchange and thermal reduction. The factors influencing the self-metallization were investigated. The electrical conductivity and integrity for the surface of the PI were achieved by optimization of ion exchange/thermal reduction parameters. The fabricated PI-matrix composite exhibits a maximum electromagnetic interference shielding effectiveness value of 81 dB. Importantly, the electromagnetic shielding performance can be maintained even after heat condition of 300°C. Meanwhile, the surface-metallized PI composite exhibits mechanical property equivalent to the pristine composite, and an Ag/matrix interfacial strength higher than 19.6 MPa. Besides, self-metallization mechanism of the thermosetting PI was investigated.

scholarly journals Electromagnetic Shielding Effectiveness of Woven Fabrics with High Electrical Conductivity: Complete Derivation and Verification of Analytical Model

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1657 ◽  
Author(s):  
Marek Neruda ◽  
Lukas Vojtech
Keyword(s):  
Electrical Conductivity ◽  
Analytical Model ◽  
Electromagnetic Interference ◽  
Woven Fabrics ◽  
Electromagnetic Shielding ◽  
High Electrical Conductivity ◽  
Shielding Effectiveness ◽  
Textile Composite ◽  
A Value ◽  
Electromagnetic Shielding Effectiveness

In this paper, electromagnetic shielding effectiveness of woven fabrics with high electrical conductivity is investigated. Electromagnetic interference-shielding woven-textile composite materials were developed from a highly electrically conductive blend of polyester and the coated yarns of Au on a polyamide base. A complete analytical model of the electromagnetic shielding effectiveness of the materials with apertures is derived in detail, including foil, material with one aperture, and material with multiple apertures (fabrics). The derived analytical model is compared for fabrics with measurement of real samples. The key finding of the research is that the presented analytical model expands the shielding theory and is valid for woven fabrics manufactured from mixed and coated yarns with a value of electrical conductivity equal to and/or higher than σ = 244 S/m and an excellent electromagnetic shielding effectiveness value of 25–50 dB at 0.03–1.5 GHz, which makes it a promising candidate for application in electromagnetic interference (EMI) shielding.

A Study of Thermal Stability and Electromaganetic Shielding Behavior of Polyaniline-P-Toluene Sulfonic Acid/Montmorillonite Nanocomposites

2011 ◽  
Vol 52-54 ◽  
pp. 180-185 ◽  
Author(s):  
Ming Kuen Chang ◽  
Hsin Hong Hsieh ◽  
Siou Jyuan Li
Keyword(s):  
Thermal Stability ◽  
Electromagnetic Interference ◽  
Conductive Polymer ◽  
Layered Silicate ◽  
Electromagnetic Shielding ◽  
Environmental Stability ◽  
Shielding Effectiveness ◽  
Increase With Increase ◽  
Toluene Sulfonic Acid ◽  
Wide Range

Intrinsically conductive polymer-Polyaniline had high conductivity and many other properties, such as environmental stability and rather simple synthesis. In addition, doping with organic acids could enhance its processing, so it had wide range of applications, such as solar cells, antistatic and electromagnetic interference shielding. In this study, the organic amine 1-Dodecylamine (DOA) modification of sodium montmorillonite (NA+-MMT), and conducting polymer / layered silicate salt nanocomposites (PANI-PTSA/DOA-MMT) had been prepared by doping aniline with organic acid (PTSA), then added organic clay. The thermal, electrical properties and EMI effects of nanocomposites had discussed by XRD, TEM, EMI, TGA analysis, conduction measure and EMI tested. The results indicated the organo-clay interlayer distance expanded from 1.29 to 1.8 nm, and DOA-MMT dispersed in the material, that formed an exfoliated nanocomposite. The thermal stability of nanocomposites depended on content of DOA-MMT, material had the better thermal stability when DOA-MMT load was 5 wt. %. The nanocomposites had the best conductivity when DOA-MMT load was 1 wt. % as well as the electromagnetic shielding effectiveness was increase with increase in conductivity. In addition, the electromagnetic shielding of nanocomposites also depended on thickness and frequency of electromagnetic wave, the electromagnetic shielding was increased with increase in thickness and frequency.

Effect of Co Concentration on Composition and Electromagnetic Shielding Properties of Ni-Co-P

2012 ◽  
Vol 214 ◽  
pp. 436-439
Author(s):  
Ming Qiu Wang ◽  
Jun Yan ◽  
Hai Ping Cui ◽  
Shi Guo Du ◽  
Yi Guo ◽  
...  
Keyword(s):  
Electromagnetic Interference ◽  
Electromagnetic Shielding ◽  
Sodium Hypophosphite ◽  
Shielding Effectiveness ◽  
Cobalt Sulfate ◽  
Silane Coupling ◽  
Co Concentration ◽  
Alkaline Bath ◽  
Shielding Properties ◽  
Electroless Ni

Electroless Ni–Co–P alloys on PVC with sodium hypophosphite as a reducing agent in an alkaline bath was investigated. Silane coupling agent (KH560) was used during the pretreatment. The morphology, chemical composition, of the electroless plating film was characterized by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The effect of Co concentration on its composition and electromagnetic shielding properties were examined. The results show that the plating rate decreased totally with increasing Co concentration. The structure of the as-plated Ni–Co–P alloys at all conditions is amorphous. When the concentration of cobalt sulfate concentration is 8g•L-1, electroless Ni–Co–P alloys exhibited better electromagnetic shielding properties, shielding effectiveness of which was 52 dB at 300 MHz. The Ni–Co–P deposits, therefore, are promising for applications in electromagnetic interference for plastics substrate.

scholarly journals Excellent Thermally Conducting Ni Plating Graphite Nanoplatelets/Poly(phenylene sulfone) Composites for High-Performance Electromagnetic Interference Shielding Effectiveness

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3493
Author(s):  
Zhang Chen ◽  
Ting Yang ◽  
Lin Cheng ◽  
Jianxin Mu
Keyword(s):  
Thermal Conductivity ◽  
Heat Conduction ◽  
Electromagnetic Interference ◽  
High Performance ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Graphite Nanoplatelets ◽  
Pressing Method ◽  
Blending Method ◽  
Thermally Conducting

First, nickel particles were deposited on the surface of graphite nanoplatelets to fabricate highly conductive GnPs@Ni core-shell structure hybrid fillers via electroplating. The modified GnPs were blended with polyphenylene sulfone via the solution blending method, followed by the hot-pressing method to achieve high thermally conducting GnPs@Ni/PPSU composites for high performance electromagnetic interference effectiveness. The results showed that in-plane and through-plane thermal conductivity of the composite at the 40 wt% filler loading could reach 2.6 Wm−1K−1 and 3.7 Wm−1K−1, respectively, which were 9.4 and 20 times higher than that of pure PPSU resin. The orientation degree of fillers was discussed by XRD and SEM. Then, heat conduction data were fitted and analyzed by the Agari model, and the heat conduction mechanism was further explored. The testing results also demonstrated that the material exhibited good conductivity, electromagnetic shielding effectiveness and superior thermal stability. Overall, the GnPs@Ni/PPSU composites had high thermal conductivity and were effective electromagnetic shielding materials at high temperatures.

Study to Wood Electromagnetic Shielding Composites Laminated with Aluminum Plates

2011 ◽  
Vol 280 ◽  
pp. 159-164 ◽  
Author(s):  
Ke Yang Lu ◽  
Feng Fu ◽  
Yue Jin Fu ◽  
Zhi Yong Cai
Keyword(s):  
Electromagnetic Interference ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Building Product ◽  
Static Modulus ◽  
Electrical Devices ◽  
Aluminum Plates ◽  
Static Modulus Of Elasticity ◽  
Electromagnetic Shielding Effectiveness ◽  
Shielding Composites

Radiations from different electrical devices cause electromagnetic interference which will influence the performance realization of other electromagnetic device and cause the health concerns. The aluminum plates were then used to develop wood electromagnetic shielding composites by laminating with the plywood. Their static modulus of elasticity and electromagnetic shielding effectiveness of the composites with different thickness and position of aluminum plates were evaluated. The results showed that the strength of composites were improved by laminating the aluminum plates on the surface. The electromagnetic shielding performance of the composites were increased by the design of the multilayer and sandwich shielding structure. Again, It was also found that the composites made by laminating two aluminum plates (1mm, in the middle or on the surface) had a better shielding effectiveness (60 dB to 92 dB, 60 dB to 106 dB, Ranged from 1 GHz to 10 GHz) and met the requirement for a commercial electromagnetic shielding building product.

The Influence of Fabric Structures of the Woven Fabrics on Electromagnetic Shielding Effectiveness

2011 ◽  
Vol 239-242 ◽  
pp. 1994-1997 ◽  
Author(s):  
Ching Wen Lou ◽  
Yi Chang Yang ◽  
Chin Mei Lin ◽  
Ching Wen Lin ◽  
Lin Chao Chen ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Electromagnetic Interference ◽  
Woven Fabrics ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Fabric Structures ◽  
Electromagnetic Shielding Effectiveness

Stainless steel (SS) blended yarns with electromagnetic interference (EMI) were made into woven fabrics, after which the fabrics were evaluated with electromagnetic shielding effectiveness (EMSE). Parameters of laminated angle and the lamination number layers affected the fabrics’ EMSE differently. In addition, density of unidirectional SS yarns affected EMSE in frequency range of 200 to 500 MHz , so as the density of cross SS yarns on a frequency over 1000 MHz.

scholarly journals Multilayer-Structured Wood Electroless Cu–Ni Composite Coatings for Electromagnetic Interference Shielding

Coatings ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 740
Author(s):  
Yanfei Pan ◽  
Dingwen Yin ◽  
Xiaofang Yu ◽  
Nanyi Hao ◽  
Jintian Huang
Keyword(s):  
Surface Roughness ◽  
Surface Morphology ◽  
Electromagnetic Interference ◽  
Composite Coatings ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Electromagnetic Interference Shielding ◽  
Electromagnetic Shielding Effectiveness ◽  
The Ideal

The lightweight multilayer-structured electromagnetic interference shielding composite coatings with controllable electromagnetic gradient on wood surface were prepared via a simple multiple electroless copper–nickel (Cu–Ni) approach. The surface morphology, conductivity, hydrophobicity property and electromagnetic shielding effectiveness of the composite coatings were investigated. The surface roughness and conductivity of the composite coatings were enhanced with the increase in the number of depositions. The surface morphology demonstrated that the roughness was decreased with the process of multiple electroless. The coatings were compact and homogeneous as the deposition run was three. Here, the Sa (Sa illustrated Surface Roughness) value of coatings was 4.497 μm. The ideal conductivity of composite coatings can be obtained as the number of depositions was four. Electromagnetic shielding effectiveness reached average 90.69 dB in the frequency range from 300 kHz to 2.0 GHz. This study provides a new pathway for fabricating lightweight multilayer-structured electromagnetic interference shielding with controllable electromagnetic gradient and hydrophobic composite coatings-based wood.

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