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This research describes a facile method to prepare durable and highly conductive polyethylene terephthalate (PET) fabrics for electromagnetic interference (EMI) shielding applications. The PET fabric surface was first coated with graphene (Gr), which converted PET to conductive Gr-PET fabric. In addition, magnetic nickel (Ni) nanoparticles were deposited on the Gr-PET substrate by an electroplating approach with different deposition time intervals (5-20 min). The surface morphology, microstructure, magnetic properties, electric conductivity, and EMIs shielding properties of the Ni/Gr-PET fabrics were ascribed as a function of the deposition times. The Ni/Gr-PET fabrics with different nickel nanoparticle morphologies display different microstructures. The manufactured Ni/Gr-PET fabrics exhibited excellent electrical conductivity and saturation magnetization of 100-134 S/cm and 14-30 emu/g, respectively. The EMI shielding efficiency of the manufactured Ni/Gr-PET fabrics with 15 min of deposition time reached -70.0 dB with a thickness of 0.33 [+ or -] 0.03 mm over the 8-12 GHz frequencies. The Ni/Gr-PET fabrics maintained relatively durable electrical properties even after cyclic bending, ultra-sonication, and treatment with organic solvents. It has been demonstrated that the properties of Ni/GrPET fabrics can be controlled by changing the surface morphology and microstructure of the nickel nanoparticles, which provides a novel protocol to manufacture PET fabrics with highly efficient EMI shielding properties. KEYWORDS durability, EMI shielding, graphene, nickel nanoparticles, textiles, 1 | INTRODUCTION Electromagnetic ([E.sub.M]) radiation is a global environmental hazard reasoned by the usage of electrical and electronic devices, and it poses a severe threat to people's health. (1-3) [...]

Recycling post‐consumer carpet waste is a critical consideration for decreasing the environmental hazard of non‐biodegradable plastics. Therefore, the manufacturing of activated carbon fibres (ACFs) from post‐consumer carpet waste treated with KOH was modelled and optimized by the response surface methodology (RSM). The simultaneous effects of carbonization rate, pyrolysis temperature, and activation time on the performance of carpet waste‐based ACFs were studied. Box–Behnken design (BBD) was applied to study the influence of three significant processing parameters on the carbon yield and iodine adsorption of synthesized ACFs. The RSM analysis established that pyrolysis temperature was the most important parameter affecting the ACFs' performance. The optimum settings that led to the production of high carbon yield and iodine adsorption of ACFs were a carbonization rate of 5.4°C/min, pyrolysis temperature of 705.7°C, and activation time of 83 min. The carbon yield and iodine adsorption under the above conditions were obtained at 49.8 ± 0.9 wt.% and 1351 ± 45 mg/g, respectively. BBD has been established to be a powerful approach in modelling and optimization to achieve high‐quality of iodine adsorbents from carpet wastes. [ABSTRACT FROM AUTHOR]

Magnetite (Fe3O4) nanoparticles/polyvinylpyrrolidone (PVP) composite nanofibers (FCNFs) have been fabricated to evaluate the potential of FCNFs as electromagnetic interference (EMI) shielding material in the frequency range of 8.2–12.4 GHz. The scanning electron microscope and viscosity analyses confirmed the presence of good dispersion Fe3O4 nanoparticles encapsulated within the electrospun nanofibers and showed FCNF morphologies with diameters of 150–500 nm. The magnetic properties and electrical conductivity of FCNFs were found to be dependent on Fe3O4 nanoparticles concentration and showed an increase with increasing Fe3O4 nanoparticles loading. The EMI shielding efficiency of FCNFs increased up to approximately 22 dB. The EMI shielding results for FCNFs showed that absorption was the major shielding mechanism and reflection was the secondary shielding mechanism. The present study has shown the possibility of utilizing magnetic FCNFs as EMI shielding/absorption materials. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs)/polyvinylpyrrolidone (PVP) composite nanofibers having varying amounts of MWCNTs were fabricated with an aim to investigate the potential of such nanofibers as an effective light weight electromagnetic interference (EMI) shielding material in the frequency range of 8.2-12.4 GHz (X-band). The state of dispersion of MWCNTs in PVP matrix was studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The TEM and SEM analyses confirmed the presence of individual dispersion MWCNTs encapsulated within the electrospun nanofibers and showed MWCNTs/PVP composite nanofiber morphologies with diameters of 150-600 nm. Moreover, the MWCNTs/PVP composite nanofibers were characterized by X-ray diffraction and Raman spectrophotometer. The thermal stability of composite nanofibers studied from thermogravimetric analysis was increased after addition of MWCNTs to PVP matrix. The EMI shielding efficiency of MWCNTs/PVP composite nanofibers increased up to 42 dB. The MWCNTs/PVP composite nanofibers developed in this study have benefits in being light weight and having effective EMI shielding performance and can be best candidates for a broad range of electronic applications. POLYM. COMPOS., 38:2026-2034, 2017. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

In this study, flexible polyurethane (PU) nanocomposite foams were prepared by in situ polymerization. The effects of incorporation of nanoparticles on the morphological and structural developments and the relation between this development and mechanical properties of the PU foam were demonstrated. The effects of three different contents (low, moderate, and high) of nanoclay and multiwall carbon nanotubes (MWNTs) loading on foam morphology, structure, kinetics of foaming reactions, and mechanical properties were separately investigated. By adding MWNTs and nanoclay in foams, the foam morphology improved, in which cell density increased and smaller cells were obtained. The mechanical properties of foam especially tensile strength have been increased in the presence of nanoparticles. With enhancing the nanoclay content, the tensile strength of nanocomposite foam has improved but in the case of MWNTs contrary effects were observed. An increase in nanoparticle amount leads to a lower cell density. In general, the incorporation of both nanoparticles (nanoclay and MWNTs) in the foam structure leads to a lower foaming reaction rate that affects mechanical properties of foams. © 2012 Wiley Periodicals, Inc. Adv Polym Techn 32: E545-E555, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21300 [ABSTRACT FROM AUTHOR]