Electromagnetic Interference Shielding Polymer Nanocomposites

Yan, Xingru; Xiang, Licheng; He, Qingliang; Gu, Junwei; Dang, Jing; Guo, Jiang; Guo, Zhanhu

doi:10.1002/9783527342501.ch19

Cited by 4 publications

(8 citation statements)

References 100 publications

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“…EMI shielding is expressed in terms of total shielding effectiveness (SE T ). SE T is defined in terms of the logarithm of the ratio of the incident power ( P I ) to the transmitted power ( P T ) through the shield material …”

Section: Resultsmentioning

confidence: 99%

“…Therefore, SE T is a summation of shielding by absorption (SE A ), shielding by reflection (SE R ), and shielding by multiple internal reflections (SE MR ) SE MR becomes insignificant when SE T > 15 dB or when the shield thickness is greater than the skin depth and SE T can then be expressed as, SE M is usually important for thin metals and at low frequency (approx. 20 kHz) …”

Section: Resultsmentioning

confidence: 99%

“…The magnitude of absorption is governed by the square root of the product of electrical conductivity and permeability of the shield material. It can also be enhanced by the increase in shield thickness and is expressed by the following equation, , where, σ represents the total conductivity, ω is the angular frequency (ω = 2π f ), μ r corresponds to the relative permeability of the shield material, and t is the thickness of the shield.…”

Section: Resultsmentioning

confidence: 99%

“…The magnitude of reflection depends on the impedance mismatch between the incident EM wave and the shield material and can be estimated using the following relation, , where, ε 0 represents the dielectric constant in free space. Thus, the reflection of EM radiation is mainly governed by the ratio of electrical conductivity and permeability of the shield material.…”

Section: Resultsmentioning

confidence: 99%

“…Carbon-based materials like carbon black, carbon fibers (CFs), carbon nanotubes (CNTs), graphene sheets (GSs), graphene nanoplates (GNP), and reduced graphene oxides (rGO) have been explored as conducting fillers for EMI shielding applications especially in the GHz frequency range. , These materials possess free electrons, which can reflect EM waves. It can further help in attenuating EM waves by multiple reflections, which eventually leads to the suppression of these waves.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Mechanistic Insight into the Nature of Dopants in Graphene Derivatives Influencing Electromagnetic Interference Shielding Properties in Hybrid Polymer Nanocomposites

Sushmita¹,

Menon²,

Sharma

et al. 2019

J. Phys. Chem. C

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The recent surge in the usage of electronics has led to a new kind of problem; electromagnetic interference which necessitates finding alternate materials that offer ease of processing, design flexibility, light weight, and ease of embedding and integrating with the existing systems in place as shields to protect the precise electronic circuitry. Herein, lightweight polycarbonate (PC)-based nanocomposites using doped graphene derivatives and multiwalled carbon nanotubes (MWCNT) has been explored for effective shielding of EM radiation in X- and Ku-band. To get a mechanistic insight as to how the dopant in graphene derivatives influences the EM shielding properties, two dopants have been explored here: ferrimagnetic (ferrite, Fe3O4) and the other one as paramagnetic (gadolinium oxide, Gd2O3). The doped graphene derivatives when composited with PC and MWCNTs resulted in materials that can shield the incoming EM radiation through magnetic and dielectric losses. This strategy of doping improves the state of dispersion of these dopants in the nanocomposites, besides enhancing the shielding effectiveness. The PC-based nanocomposites illustrated a total shielding effectiveness (SET) of −28 and −33 dB at 18 GHz for a given concentration of Gd2O3 and Fe3O4 hybrid, respectively. A closer look into the mechanism of shielding reveals that irrespective of the dopant, various losses (magnetic and dielectric) decide the shielding effectiveness in polymeric nanocomposites facilitated by multiple internal reflections. Taken together, this study brings in new insight as to how the losses contribute toward effective shielding rather than the choice of the dopant and will help guide researchers working in this area from both industrial as well as academic perspective.

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Mechanistic Insight into the Nature of Dopants in Graphene Derivatives Influencing Electromagnetic Interference Shielding Properties in Hybrid Polymer Nanocomposites

Sushmita¹,

Menon²,

Sharma

et al. 2019

J. Phys. Chem. C

View full text Add to dashboard Cite

show abstract

Optimizing electromagnetic interference shielding ofcarbon nanofibersreinforced nylon 6, 6 nanocomposite films in terahertz range

Arooj

Mumtaz

Rehman

et al. 2023

J of Applied Polymer Sci

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The widespread development and usage of electrical and electronic devices in THz frequency band has instigated great concerns regarding the anticipated functioning of devices. The world is in dire need to develop tunable shielding materials which are not only field functional but could also provide shielding against undesired electromagnetic signals by absorption as the primary mechanism. In this work, nylon 6,6 based hybrid nanocomposite films loaded with 0–50 wt% CNFs have been prepared on the cellulosic substrates by air spray coating technique. XRD and FESEM results have established formation of crystalline films having homogeneously distributed CNFs in the polymer matrix leading to formation of an efficient conductive network. IV measurements demonstrate a significant rise in the dc conductivity in the polymer nanocomposite samples with the gradual increase of CNF content in comparison to the pristine sample. Interestingly, sample containing 50 wt% CNFs has shown dc conductivity value of 0.03 Scm−1 while shielding effectiveness (SE) of 44 dB obtained through THz‐TDS. The results hold a distinctive position in these samples which have outperformed at a very low thickness of ~570 μm as compared to the results obtained by many other novel polymer composites and present themselves a light weight field functional high THz absorption materials.

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Intrinsically conducting polymer-based nanocomposite aerogels for electromagnetic interference shielding

Hosseini,

firouzan,

Seyed Dorraji

2024

Porous Nanocomposites for Electromagnetic Interference Shielding

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Electromagnetic Interference Shielding Polymer Nanocomposites

Cited by 4 publications

References 100 publications

Mechanistic Insight into the Nature of Dopants in Graphene Derivatives Influencing Electromagnetic Interference Shielding Properties in Hybrid Polymer Nanocomposites

Mechanistic Insight into the Nature of Dopants in Graphene Derivatives Influencing Electromagnetic Interference Shielding Properties in Hybrid Polymer Nanocomposites

Optimizing electromagnetic interference shielding ofcarbon nanofibersreinforced nylon 6, 6 nanocomposite films in terahertz range

Intrinsically conducting polymer-based nanocomposite aerogels for electromagnetic interference shielding

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