Polyurethane/Graphite composite foam samples with different filler loadings were synthesized for application in electromagnetic shielding. The samples were characterized using Fourier transform infra‐red, thermal gravimetric analysis, scanning electron microscope, universal testing machine, and rheometer. Moreover, to adapt and customize this work in the field of aerospace, the measurements were performed in the X‐band at the range of (8–12) GHz. The results showed that the increase in filler content improves the mechanical properties and thermal stability of the composite materials. The electromagnetic interference shielding effectiveness reached (− 45) dB with 30 wt% filler content. It is expected that the polyurethane/graphite composite foamy materials may be considered a promising material to be used in electromagnetic shielding applications.

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Poly ionic liquids (PIL) are eco-friendly in addition to being sustainable compounds that can be easily prepared and tailored according to the application. In this study, a novel PIL polymer based on acrylate was chemically synthesised via free radical polymerization method controlled by quenching the reversible reaction. The prepared 1-Butyl-3 Methylimidazolium Acrylate polymer (PAL) was characterised using FTIR as well as NMR to confirm the chemical structure. GPC was employed to determine the average molecular weight of the new polymer. PAL was applied as an effective corrosion inhibitor for C1020 steel in 1M HCl aqueous solution. Weight loss and electrochemical techniques, PDP and EIS, were applied to evaluate the corrosion inhibition performance. The electrochemical results showed that PAL acts as a mixed-type inhibitor reaches 91.8% at room temperature. The thermodynamic calculations showed that the adsorption process is exothermic. Furthermore, PAL molecules were adsorbed on the metal surface by both chemisorption and physisorption processes. SEM analysis was carried out to confirm the corrosion evaluation results. Also, quantum chemical calculations, at the B3LYP/DND level of theory, were carried out to correlate the electronic structure parameters of PAL inhibitor to its adsorption behaviour which in turn is relevant to the inhibition efficiency. Additionally, Monte Carlo simulation (MC) was conducted to investigate the adsorption modes and the interaction energies of the inhibitor on iron surface.

Reduced graphene oxide (RGO) is an effective polymer filler for shielding against electromagnetic interference (EMI). Its shielding efficiency rises as its concentration in polymer matrices increases. However, higher filler loading impedes polymer foaming and deteriorates the mechanical properties of the resulting foam. The goal of this work is to determine the optimal RGO concentration that can be loaded into polyurethane (PU) matrix to produce a composite foam with a high level of electromagnetic shielding along with good mechanical properties. To that end, different PU foam samples containing varying amounts of RGO were synthesized. The synthesized samples were characterized by scanning electron microscope (SEM), thermogravimetric analysis (TGA), Fourier transform infra-red (FT/IR) and universal testing machine. Furthermore, the shielding efficiency of the samples was measured using a vector network analyzer over the frequency range of 8-12 GHz. The results revealed that the increase in RGO concentration enhances the mechanical and thermal properties of the prepared composite foam materials. The shielding effectiveness reached À23 dB at 5 wt% RGO concentration. The polyurethane-RGO composite foam materials have been identified as potentially viable materials for use in electromagnetic shielding applications.

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