Light-Weight Multi-Walled Carbon Nanotube Buckypaper/Glass Fiber-Epoxy Composites for Strong Electromagnetic Interference Shielding and Efficient Microwave Absorption

Abstract Multi-walled carbon nanotube buckypaper (BP) reinforced glass fiber-epoxy (GF/EP) composites were selected to fabricate electromagnetic interference (EMI) shielding and microwave absorbing composites. Six different composite configurations with 3.0 mm thick have been conceived and tested over the X-band (8.2-12.4 GHz). Flexible and low density (0.29 g/cm3) BP provided a high specific EMI SE of 55 dB with controlled electrical conductivity. GF/EP/BP111 and GF/EP/BP101 composites possess EMI SE as high as of 50-60 dB, which can be attributed to the number of BP inserted and variation in the wave-transmitting layer of the laminates. Furthermore, the shielding mechanism was discussed, and it suggested that the dominant contribution to EMI SE was absorption. GF/EP/BP110 laminate demonstrated suitable EMI performance (~20 dB) and excellent microwave performance, achieving an effective -10 dB bandwidth of 3.04 GHz and minimum reflection loss (RL) value of -21.16 dB at 10.37 GHz. On the basis of these results, GF/EP/BP composites prepared in this work have potential applications as both EMI shielding and microwave absorber materials given their facile preparation and lightweight use.

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Preparation and Study of Electromagnetic Interference Shielding Materials Comprised of Ni-Co Coated on Web-Like Biocarbon Nanofibers via Electroless Deposition

Journal of Nanomaterials ◽

10.1155/2015/320306 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 13

Author(s):

Xiaohu Huang ◽

Bo Dai ◽

Yong Ren ◽

Jing Xu ◽

Pei Zhu

Keyword(s):

Electromagnetic Interference ◽

Electroless Deposition ◽

Paraffin Wax ◽

Matrix Composites ◽

Emi Shielding ◽

Electromagnetic Interference Shielding ◽

Electrical Conductivities ◽

Potential Applications ◽

Emi Se ◽

Factor Governing

Electromagnetic interference (EMI) shielding materials made of Ni-Co coated on web-like biocarbon nanofibers were successfully prepared by electroless plating. Biocarbon nanofibers (CF) with a novel web-like structure comprised of entangled and interconnected carbon nanoribbons were obtained using bacterial cellulose pyrolyzed at 1200°C. Paraffin wax matrix composites filled with different loadings (10, 20, and 30 wt%, resp.) of CF and Ni-Co coated CF (NCCF) were prepared. The electrical conductivities and electromagnetic parameters of the composites were investigated by the four-probe method and vector network analysis. From these results, the EMI shielding efficiencies (SE) of NCCF composites were shown to be significantly higher than that of CF at the same mass fraction. The paraffin wax composites containing 30 wt% NCCF showed the highest EMI SE of 41.2 dB (99.99% attenuation), which are attributed to the higher electrical conductivity and permittivity of the NCCF composites than the CF composites. Additionally, EMI SE increased with an increase in CF and NCCF loading and the absorption was determined to be the primary factor governing EMI shielding. This study conclusively reveals that NCCF composites have potential applications as EMI shielding materials.

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Lightweight, flexible and thin Fe3O4-loaded, functionalized multi walled carbon nanotube buckypapers for enhanced X-band electromagnetic interference shielding

Materials Research Express ◽

10.1088/2053-1591/aa69f4 ◽

2017 ◽

Vol 4 (4) ◽

pp. 045012 ◽

Cited By ~ 6

Author(s):

B V Bhaskara Rao ◽

Mithali Chengappa ◽

S N Kale

Keyword(s):

Carbon Nanotube ◽

Electromagnetic Interference ◽

Electromagnetic Interference Shielding ◽

Multi Walled Carbon Nanotube ◽

X Band

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Ultralow percolation threshold and enhanced electromagnetic interference shielding in poly(l-lactide)/multi-walled carbon nanotube nanocomposites with electrically conductive segregated networks

Journal of Materials Chemistry C ◽

10.1039/c7tc02948a ◽

2017 ◽

Vol 5 (36) ◽

pp. 9359-9369 ◽

Cited By ~ 239

Author(s):

Kai Zhang ◽

Gen-Hui Li ◽

La-Mei Feng ◽

Ning Wang ◽

Jiang Guo ◽

...

Keyword(s):

Carbon Nanotube ◽

Percolation Threshold ◽

Electromagnetic Interference ◽

High Performance ◽

Emi Shielding ◽

Electromagnetic Interference Shielding ◽

Electrically Conductive ◽

Multi Walled Carbon Nanotube

Segregated PLLA/MWCNTs nanocomposites were synthesized with high-performance EMI shielding.

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Polyaniline-Stannous Oxide Composites: Novel Material for Broadband EMI Shielding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.488-489.557 ◽

2012 ◽

Vol 488-489 ◽

pp. 557-561 ◽

Cited By ~ 8

Author(s):

Muhammad Faisal ◽

Syed Khasim

Keyword(s):

Electromagnetic Interference ◽

Chemical Oxidation ◽

Shielding Effectiveness ◽

Emi Shielding ◽

Practical Applications ◽

Stannous Oxide ◽

Emi Shielding Effectiveness ◽

X Band ◽

Potential Applications ◽

Emi Se

Insitu polymerization of aniline was carried out in the presence of stannous oxide (SnO) to synthesize Polyaniline (PAni)/SnO composites by chemical oxidation method. The surface morphology of the composites were studied by scanning electron microscopy (SEM).The electromagnetic interference (EMI) shielding properties of the composites were investigated for different wt % of SnO (10,20,30,40 and 50 wt%) in PAni. The EMI measurements were carried out in the frequency range from 8.2 to 12.4 GHz (X-band), which is relevant for practical applications. EMI shielding effectiveness (EMI SE), microwave absorption and reflection, the influence of SnO concentration in PAni on EMI SE of the composites are reported. The composites exhibit EMI SE value of -18 to -23 dB. The absorption dominated EMI SE of these composites indicates the potential applications of these materials for microwave attenuation in the X-band.

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Electrical Conductivity and Electromagnetic Interference Shielding of Multi-walled Carbon Nanotube Filled Polymer Composites

MRS Proceedings ◽

10.1557/proc-858-hh5.3 ◽

2004 ◽

Vol 858 ◽

Cited By ~ 1

Author(s):

Yonglai Yang ◽

Mool C. Gupta ◽

Kenneth L. Dudley ◽

Roland W. Lawrence

Keyword(s):

Carbon Nanotube ◽

Electromagnetic Interference ◽

Shielding Effectiveness ◽

Emi Shielding ◽

Frequency Range ◽

Sem Images ◽

Percolation Behavior ◽

Multi Walled Carbon Nanotube ◽

X Band ◽

Conducting Networks

ABSTRACTMulti-walled carbon nanotube (MWNT) filled polystyrene (PS) composites were synthesized for electromagnetic interference (EMI) shielding applications. SEM images of composites showed the formation of the conducting networks through MWNTs within the PS matrix. The measured DC conductivity of composites increased with increasing MWNT loading, showing a typical percolation behavior. EMI shielding characteristics of MWNT-PS composites were investigated in the frequency range of 8.2–12.4 GHz (X-band). It was observed that the shielding effectiveness (SE) of such composite increased with the increase of MWNT loading. The SE of the composite containing 7 wt% MWNTs could reach more than 26 dB in the measured frequency region.

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Ultrathin, Lightweight, and Flexible CNT Buckypaper Enhanced Using MXenes for Electromagnetic Interference Shielding

Nano-Micro Letters ◽

10.1007/s40820-021-00597-4 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Rongliang Yang ◽

Xuchun Gui ◽

Li Yao ◽

Qingmei Hu ◽

Leilei Yang ◽

...

Keyword(s):

Electromagnetic Interference ◽

High Performance ◽

Electronic Devices ◽

Deposition Process ◽

Shielding Effectiveness ◽

Emi Shielding ◽

Emi Shielding Effectiveness ◽

X Band ◽

Wearable Electronic Devices ◽

Emi Se

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.

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A Healable and Mechanically Enhanced Composite with Segregated Conductive Network Structure for High-Efficient Electromagnetic Interference Shielding

Nano-Micro Letters ◽

10.1007/s40820-021-00693-5 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Ting Wang ◽

Wei-Wei Kong ◽

Wan-Cheng Yu ◽

Jie-Feng Gao ◽

Kun Dai ◽

...

Keyword(s):

Electromagnetic Interference ◽

Diels Alder ◽

Electrostatic Attraction ◽

List Type ◽

Shielding Effectiveness ◽

Emi Shielding ◽

Electromagnetic Interference Shielding ◽

Elongation At Break ◽

High Efficient ◽

Emi Se

Highlights The cationic waterborne polyurethanes microspheres with Diels-Alder bonds were synthesized for the first time. The electrostatic attraction not only endows the composite with segregated structure to gain high electromagnetic-interference shielding effectiveness, but also greatly enhances mechanical properties. Efficient healing property was realized under heating environment. Abstract It is still challenging for conductive polymer composite-based electromagnetic interference (EMI) shielding materials to achieve long-term stability while maintaining high EMI shielding effectiveness (EMI SE), especially undergoing external mechanical stimuli, such as scratches or large deformations. Herein, an electrostatic assembly strategy is adopted to design a healable and segregated carbon nanotube (CNT)/graphene oxide (GO)/polyurethane (PU) composite with excellent and reliable EMI SE, even bearing complex mechanical condition. The negatively charged CNT/GO hybrid is facilely adsorbed on the surface of positively charged PU microsphere to motivate formation of segregated conductive networks in CNT/GO/PU composite, establishing a high EMI SE of 52.7 dB at only 10 wt% CNT/GO loading. The Diels–Alder bonds in PU microsphere endow the CNT/GO/PU composite suffering three cutting/healing cycles with EMI SE retention up to 90%. Additionally, the electrostatic attraction between CNT/GO hybrid and PU microsphere helps to strong interfacial bonding in the composite, resulting in high tensile strength of 43.1 MPa and elongation at break of 626%. The healing efficiency of elongation at break achieves 95% when the composite endured three cutting/healing cycles. This work demonstrates a novel strategy for developing segregated EMI shielding composite with healable features and excellent mechanical performance and shows great potential in the durable and high precision electrical instruments.

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