Enhanced microwave shielding and mechanical properties of multiwall carbon nanotubes anchored carbon fiber felt reinforced epoxy multiscale composites

Abstract

Multi-walled carbon nanotubes (MWCNTs) were grown on carbon fiber (CF) felt by chemical vapor deposition that resulted into strongly anchored carbon nanotubes (CNTs) on the CF surface. These multiscale preforms were used as the reinforcement in epoxy resin to develop multi scale CF felt-MWCNT/epoxy composites. The flexural strength (FS) and the flexural modulus (FM) of the composites were found to increase with increasing amount of CNTs grown on CF felt surface. FS improved by 37 %, i.e. 119 MPa compared to 87 MPa for CF felt/epoxy composites prepared under identical conditions. The FM also improved by 153 %, i.e. 15.7 GPa compared to 6.2 GPa for the CF/epoxy composites. The incorporation of MWCNTs on the CF felt produced a significant change in the electromagnetic interference shielding of these composites which improved from -21 to -27 dB for CF felt-MWCNT/epoxy multiscale composites in the Ku band (12.4-18 GHz) and indicates the usefulness of these strong composites for microwave shielding.

Polyaromatic-hydrocarbon-based carbon copper composites for the suppression of electromagnetic pollution

“…As the commercial applications of EMI shielding material requires a SE value of at least around 30 dB, 3 our Cu-coated HTPAHs-derived nanocomposites can be employed for commercial EMI shielding applications with an appropriate Cu nanoparticle loading. Our values of EMI shielding are much better than those of typical carbon materials, such as multi-wall carbon nanotubes anchored carbon ber, 40 graphene epoxy composite, 41 and other carbon materials, 9 etc. Fig.…”

Multi-walled carbon nanotube–graphene–polyaniline multiphase nanocomposite with superior electromagnetic shielding effectiveness

“…EMI shielding refers to the reection and absorption of electromagnetic radiation by the material. 25,31,32 In the case of reection of the radiation by the shielding material, the shield material must have a mobile charge carrier (electron or holes) which interacts with the electromagnetic eld in the radiation. As a result, the shield material tends to be electrically conducting.…”

Improved microwave shielding properties of polyaniline grown over three-dimensional hybrid carbon assemblage substrate

“…The EMI shielding is a direct result of reflection, absorption and multiple internal reflection losses at the existing interfaces, suffered by incident electromagnetic (EM) waves. EMI shielding effectiveness can be expressed as (Das et al 2000;Saini et al 2009Saini et al , 2011Singh et al 2013) follows:…”

“…It is, therefore, vital to develop new materials with enhanced EMI shielding capacity. It is well known that the shield should be conducting; therefore, usually the shielding techniques focus on the use of standard metals and their composites which have shortcomings of limited mechanical flexibility, heavy weight, corrosion, physical rigidity and difficulty in tuning the shielding efficiency Singh et al 2013;Pande et al 2009;Qin et al 2010). Further, metals mainly reflect the radiation and cannot be used in applications where absorption is the prime requisite.…”

“…On account of various tremendous properties of conducting polymers, CNTs and graphene, it is reasonable to develop a nanostructure hybrid composite so that the properties of the materials can be enhanced and the composite can be used for advanced applications. The authors Gupta et al (2014), Saini et al (2009), Singh et al (2013 and Pande et al (2009) reported the EMI shielding properties with the variations in the filler loadings (MWCNTs and graphene), whereas, in this work, we investigated the effect on conductivity and EMI shielding properties of the composite materials obtained by varying the mole content of aniline monomer in the initial polymerization solution.…”