Does the Type of Polymer and Carbon Nanotube Structure Control the Electromagnetic Shielding in Melt-Mixed Polymer Nanocomposites?

Abstract

A suitable polymer matrix and well dispersed conducting fillers forming an electrically conducting network are the prime requisites for modern age electromagnetic shield designing. An effective polymer-based shield material is designed that can attenuate 99.9% of incident electromagnetic (EM) radiation at a minimum thickness of <0.5 mm. This is accomplished by the choice of a suitable partially crystalline polymer matrix while comparing non-polar polypropylene (PP) with polar polyvinylidene fluoride (PVDF) and a best suited filler nanomaterial by comparing different types of carbon nanotubes such as; branched, single-walled and multi-walled carbon nanotubes, which were added in only 2 wt %. Different types of interactions (polar-polar and CH-π and donor-acceptor) make b-MWCNT more dispersible in the PVDF matrix, which together with high crystallinity resulted in the best electrical conductivity and electromagnetic shielding ability of this composite. This investigation additionally conceals the issues related to the thickness of the shield material just by stacking individual thin nanocomposite layers containing different carbon nanotube (CNT) types with 0.3 mm thickness in a simple manner and finally achieves 99.999% shielding efficiency at just 0.9 mm thickness when using a suitable order of the different PVDF based nanocomposites.

Tuning Electromagnetic Interference Shielding Performance through Controlled Alignment of Ni Nanowires in Soft PDMS Composites

“…It has also been noted that, even in the absence of electric fields, the MWCNTs tend to attract each other in the PDMS matrix during curing due to the intertube van der Waals forces. 34,35 Therefore, we propose that the in-plane bulk alignment of the MWCNTs network followed immediately after the alignment of magneto-responsive Ni-NWs along the perpendicular direction of the magnetic field, H. During the initial alignment of Ni-NWs, the individual MWCNT started to mobilize in the in-plane direction, thereby forming bundles. Consequently, a robust electrically conducting network was formed by means of the primary alignment of magnetic Ni-NWs.…”

X‐band dielectric properties of hybrid nanocomposites of nitrogen‐doped carbon nanotube/functionalized nanoclay/polyvinylidene fluoride nanocomposite

“…[ 53 ] PVDF has a polar nature, and the presence of strongly electrophilic fluorine groups in the PVDF molecular structure can lead to a strong interaction between PVDF chains and CNTs. [ 54,55 ] To attain a homogeneous dispersion of N‐CNTs in the PVDF matrix, melt mixing was used to increase the interfacial area between the polymer chains and N‐CNTs via intense shear forces at high temperatures. [ 55 ] The polymer and nanofillers were melt‐mixed in an Alberta Polymer Asymmetric Minimixer (APAM) operated at temperature of 240°C and rotor speed of 235 rpm (this is the maximum rpm for the mixer).…”

Cellulose‐Based Sustainable Composites: A Review of Systems for Applications in EMI Shielding and Sensors

“…Several polymer-based composites have been used to design EMI shielding materials, highlighting the significance of polymers in the fabrication of shielding materials. [5] Cellulose is a naturally abundant renewable polymeric material with various applications, [6][7][8] particularly in lightweight electronic materials. Aerospace and automobile industries usually require lightweight EMI shielding materials as lightness is an important technical factor in these industries.…”

“…Several polymer‐based composites have been used to design EMI shielding materials, highlighting the significance of polymers in the fabrication of shielding materials. [ 5 ]…”