scholarly journals Simulation and Optimization of Electromagnetic Absorption of Polycarbonate/CNT Composites Using Machine Learning

Micromachines ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 778
Author(s):  
Lakhdar Sidi Salah ◽  
Mohamed Chouai ◽  
Yann Danlée ◽  
Isabelle Huynen ◽  
Nassira Ouslimani

Electronic devices that transmit, distribute, or utilize electrical energy create electromagnetic interference (EMI) that can lead to malfunctioning and degradation of electronic devices. EMI shielding materials block the unwanted electromagnetic waves from reaching the target material. EMI issues can be solved by using a new family of building blocks constituted of polymer and nanofillers. The electromagnetic absorption index of this material is calculated by measuring the “S-parameters”. In this article, we investigated the use of artificial intelligence (AI) in the EMI shielding field by developing a new system based on a multilayer perceptron neural network designed to predict the electromagnetic absorption of polycarbonate-carbon nanotubes composites films. The proposed system included 15 different multilayer perception (MLP) networks; each network was specialized to predict the absorption value of a specific category sample. The selection of appropriate networks was done automatically, using an independent block. Optimization of the hyper-parameters using hold-out validation was required to ensure the best results. To evaluate the performance of our system, we calculated the similarity error, precision accuracy, and calculation time. The results obtained over our database showed clearly that the system provided a very good result with an average accuracy of 99.7997%, with an overall average calculation time of 0.01295 s. The composite based on polycarbonate−5 wt.% carbon nanotube was found to be the ultimate absorber over microwave range according to Rozanov formalism.

2015 ◽  
Vol 3 (26) ◽  
pp. 6589-6599 ◽  
Author(s):  
Mao-Sheng Cao ◽  
Xi-Xi Wang ◽  
Wen-Qiang Cao ◽  
Jie Yuan

Ultrathin graphene, a 2D material, demonstrates outstanding features and rapid growth for EMI shielding due to its strong absorption towards electromagnetic waves in composites. It is sought after for communication, electronic devices, information security, electromagnetic pollution defense and healthcare.


2021 ◽  
pp. 152808372110370
Author(s):  
Faiza Safdar ◽  
Munir Ashraf ◽  
Amjed Javid ◽  
Kashif Iqbal

The rapid proliferation of electronic devices and their operation at high frequencies has raised the contamination of artificial electromagnetic radiations in the atmosphere to an unprecedented level that is responsible for catastrophe for ecology and electronic devices. Therefore, the lightweight and flexible electromagnetic interference (EMI) shielding materials are of vital importance for controlling the pollution generated by such high-frequency EM radiations for protecting ecology and human health as well as the other nearby devices. In this regard, polymeric textile-based shielding composites have been proved to be the best due to their unique properties such as lightweight, excellent flexibility, low density, ease of processability and ease of handling. Moreover, such composites cover range of applications from everyday use to high-tech applications. Various polymeric textiles such as fibers, yarn, woven, nonwoven, knitted, as well as their hybrid composites have been extensively manipulated physically and/or chemically to act as shielding against such harmful radiations. This review encompasses from basic concept of EMI shielding for beginner to the latest research in polymeric-based textile materials synthesis for experts, covering detailed mechanisms with schematic illustration. The review also covers the gap of materials synthesis and their application on polymeric textiles which could be used for EMI shielding applications. Furthermore, recent research regarding rendering EMI shielding properties at various stages of polymeric textile development is provided for readers with critical analysis. Lastly, the applications along with environmental compliance have also been presented for better understanding.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Rongliang Yang ◽  
Xuchun Gui ◽  
Li Yao ◽  
Qingmei Hu ◽  
Leilei Yang ◽  
...  

AbstractLightweight, flexibility, and low thickness are urgent requirements for next-generation high-performance electromagnetic interference (EMI) shielding materials for catering to the demand for smart and wearable electronic devices. Although several efforts have focused on constructing porous and flexible conductive films or aerogels, few studies have achieved a balance in terms of density, thickness, flexibility, and EMI shielding effectiveness (SE). Herein, an ultrathin, lightweight, and flexible carbon nanotube (CNT) buckypaper enhanced using MXenes (Ti3C2Tx) for high-performance EMI shielding is synthesized through a facile electrophoretic deposition process. The obtained Ti3C2Tx@CNT hybrid buckypaper exhibits an outstanding EMI SE of 60.5 dB in the X-band at 100 μm. The hybrid buckypaper with an MXene content of 49.4 wt% exhibits an EMI SE of 50.4 dB in the X-band with a thickness of only 15 μm, which is 105% higher than that of pristine CNT buckypaper. Furthermore, an average specific SE value of 5.7 × 104 dB cm2 g−1 is exhibited in the 5-μm hybrid buckypaper. Thus, this assembly process proves promising for the construction of ultrathin, flexible, and high-performance EMI shielding films for application in electronic devices and wireless communications.


2020 ◽  
Vol 20 (5) ◽  
pp. 2847-2857
Author(s):  
Madhvi Tiwari ◽  
M. A. Arya ◽  
Priyesh V. More ◽  
Saurabh Parmar ◽  
Suwarna Datar ◽  
...  

The magnetic properties of the metal nanoparticles (NPs) can play remarkable role in electromagnetic interference shielding (EMI Shielding) of many defence and commercial electronic devices. In the present work, coconut oil and PVA capped magnetic cobalt/cobalt oxide nanoparticles (Co/Co3O4 NPs) were synthesized by chemical reduction method and impregnated in polymer matrix to verify their EMI shielding behaviour. The coconut oil capped Co/Co3O4 NPs with presence of hcp and fcc phases were prepared in the size domain of 7–10 nm and the effect of surfactant (the oil) on size and oxidation state was studied by varying the ratios. The shielding efficiencies of Co/Co3O4 NPs PVA nanocomposites were analysed by using vector network analyser (VNA) in X- and Ku-band ranging from 8 GHz–18 GHz. The VNA results showed increased shielding efficiency with increasing concentration of NPs.


2020 ◽  
pp. 089270572092512
Author(s):  
Ahsan Nazir

The extensive growth of telecommunication and electronic devices has led to significant concerns regarding electromagnetic (EM) radiations. Thus, the effect of EM radiations can be reduced by using highly efficient shielding materials. This review aimed to explore the electromagnetic interference (EMI) shielding materials based on polyvinylidene fluoride (PVDF), polyurethane (PU), and polyaniline (PANI) composites. It was found that the composites based on PVDF, PU, and PANI polymers have attracted considerable interest and highly efficient for EMI shielding due to their remarkable properties like lightweight, thermal stability, processing benefits, cheap, tremendous flexibility, and excellent resistance to corrosion. Hence, the PVDF-, PU-, and PANI-based composites are efficient EMI shielding materials.


RSC Advances ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 1419-1427 ◽  
Author(s):  
Shaofeng Lin ◽  
Su Ju ◽  
Jianwei Zhang ◽  
Gang Shi ◽  
Yonglyu He ◽  
...  

As the demand for wearable and foldable electronic devices increases rapidly, ultrathin and flexible thermal conducting films with exceptional electromagnetic interference (EMI) shielding effectiveness (SE) are greatly needed.


Polymers ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 933 ◽  
Author(s):  
Fang Ren ◽  
Zheng-Zheng Guo ◽  
Han Guo ◽  
Li-Chuan Jia ◽  
Yu-Chen Zhao ◽  
...  

In this work, we propose novel layer-structured polymer composites (PCs) for manipulating the electromagnetic (EM) wave transport, which holds unique electromagnetic interference (EMI) shielding features. The as-prepared PCs with a multilayered structure exhibits significant improvement in overall EMI shielding effectiveness (EMI SE) by adjusting the contents and distribution of electrical and magnetic loss fillers. The layer-structured PCs with low nanofiller content (5 wt % graphene nanosheets (GNSs) and 15 wt % Fe3O4) and a thickness of only 2 mm exhibited ultrahigh electrical conductivity and excellent EMI SE, reaching up to 2000 S/m and 45.7 dB in the X-band, respectively. The increased EMI SE of the layer-structured PCs was mainly based on the improved absorption rather than the reflection of electromagnetic waves, which was attributed to the “absorb-reflect-reabsorb” process for the incident electromagnetic waves. This work may provide a simple and effective approach to achieve new EMI shielding materials, especially for absorption-dominated EMI shielding.


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2856
Author(s):  
Klaudia Zeranska-Chudek ◽  
Anna Wróblewska ◽  
Sebastian Kowalczyk ◽  
Andrzej Plichta ◽  
Mariusz Zdrojek

In the age of mobile electronics and increased aerospace interest, multifunctional materials such as the polymer composites reported here are interesting alternatives to conventional materials, offering reduced cost and size of an electrical device packaging. We report a detailed study of an ecological and dual-functional polymer composite for electromagnetic interference (EMI) shielding and heat management applications. We studied a series of polylactic acid/graphene nanoplatelet composites with six graphene nanoplatelet loadings, up to 15 wt%, and three different flake lateral sizes (0.2, 5 and 25 μm). The multifunctionality of the composites is realized via high EMI shielding efficiency exceeding 40 dB per 1 mm thick sample and thermal conductivity of 1.72 W/mK at 15 wt% nanofiller loading. The EMI shielding efficiency measurements were conducted in the microwave range between 0.2 to 12 GHz, consisting of the highly relevant X-band (8–12 GHz). Additionally, we investigate the influence of the nanofiller lateral size on the studied physical properties to optimize the studied functionalities per given nanofiller loading.


CORROSION ◽  
10.5006/3384 ◽  
2020 ◽  
Vol 76 (4) ◽  
pp. 411-423 ◽  
Author(s):  
Youliang He

Electromagnetic interference (EMI) shielding is a common technology used to protect electronic devices from the interference of environmental noise or to prevent the radiation of electromagnetic waves from electronic devices to the environment. In this research, the EMI shielding principle was utilized to develop a simple and cost-effective wireless corrosion-monitoring sensor. A thin metal sheet (e.g., a steel foil) similar to the material to be monitored was attached onto the surface of a radio frequency identification (RFID) transponder and served as an RF shielding layer to block the communication between the RFID transponder and the transceiver. The shielded transponder (the sensor) was then subjected to corrosion exposure, which caused the corrosion of the shielding metal sheet and led to the degradation of the shielding effectiveness. By chronically recording the change of the RF signal strength and the amount of corrosion that occurred, a correlation could be established between the signal strength and the corrosion rate. In this way, a simple wireless corrosion-monitoring sensor was developed. Steel sheets with various thicknesses (50 μm to 250 μm) were used as shielding layers on ultra-high-frequency RFID transponders, and the sensors covered by these various sheets behaved differently during corrosion exposure. The microstructure change of the shielding material was characterized by optical microscopy and scanning electron microscopy, which revealed the uneven thinning and final damage of the shielding layer, leading to the (partial) restoration of the RF signal.


Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 738
Author(s):  
Hyun-Seok Choi ◽  
Su-Jeong Suh ◽  
Sang-Woo Kim ◽  
Hyun-Joong Kim ◽  
Ji-Won Park

Utilization of methods involving component integration has accelerated, owing to the growth of the smart mobile industry. However, this integration leads to interference issues between the components, thereby elucidating the importance of the electromagnetic interference (EMI) shielding technology to solve such issues. EMI shielding technology has been previously implemented via the reflection or absorption of electromagnetic waves by using conductive materials. Nevertheless, to tackle the recent changes in the industry, a transparent and flexible EMI shielding technology is necessitated. In this study, a transparent and flexible EMI shielding material was fabricated by filling a conductive binder in a film comprising an intaglio pattern; this was achieved by using the ultraviolet (UV) imprinting technology to realize mass production. Subsequently, changes in the aperture ratio and shielding characteristics were analyzed according to the structure of the pattern. Based on this analysis, a square pattern was designed and a film with an intaglio pattern was developed through a UV imprinting process. Furthermore, it was confirmed that the transmittance, conductivity, and EMI shielding rate of the film were altered while changing the coating thickness of the conductive particles in the intaglio pattern. The final film prepared in this study exhibited characteristics that satisfied the required EMI shielding performance for electric and electronic applications, while achieving flexible structural stability and transparency.


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