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Electromagnetic radiation (EMR) pollution is a serious concern in today's environment, causing problems not just for electronic gadgets but also for living society. The goal of this research is to fabricate thermoplastic polyurethane (TPU) and polypyrrole (PPy)-based 95:5 blend nanocomposites using a simple solvent casting method at such a low concentration of rGO and MWCNT (0.3, 0.4, 0.5 php) (parts per hundred polymers), for electromagnetic wave (EMW) absorption applications. The chemical interaction between the different phases and morphology of the nanocomposites is characterized by Raman spectroscopy, X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM) techniques. The material properties, such as dielectric and magnetic properties, are analyzed in X-band frequency (8.2-12.4 GHz). The total shielding effectiveness of (SETot) 0.5 rGO system is found to be 27 dB, whereas, for corresponding MWCNT nanocomposites, it is 26 dB. Interestingly, in 0.5 rGO nanocomposites, absorption shielding effectiveness (SEAbs) is approximately 25 dB, and reflection shielding effectiveness (SERef) is less than 2 dB, which indicates the absorption of 70% of the electromagnetic wave, and the rest gets reflected. Apart from that, the rGO-based nanocomposites possess a greater extent of thermal stability than the corresponding MWCNT-based nanocomposites. Highlights • Fabrication of TPU-PPy-rGO and TPU-PPy-MWCNT nanocomposites by solvent casting. • Low reflection of TPU-PPy-rGO nanocomposites with a 70% absorption rate. • FESEM confirms the multilayer interface structures. • Tunable Dielectric and magnetic properties of nanocomposites in X-band. • Excellent absorption dominant properties of the fabricated nanocomposites. [ABSTRACT FROM AUTHOR]

Conductive polymer nanocomposites are enormously potent multifunctional lightweight flexible materials used in various electronic devices owing to their excellent dielectric characteristics with interesting relaxation behavior. In this present context, dielectric properties like dielectric permittivity (ε′), dielectric loss (ε″), AC conductivity (σac), real and imaginary impedance (Z′ and Z″), Nyquist plots, etc., of thermoplastic polyurethane/polyaniline/TiO2 (TPU/PANI/TiO2) nanocomposite films with 0–2 wt% TiO2 loading level have been studied. The dielectric analysis in the frequency range of 1 Hz to 1 MHz reveals that ε', σac, Nyquist plot as well as the relaxation behavior have been effectively tuned up to 1.5 wt% TiO2 loading level. The very high interfacial polarization of the dipoles at the interface is reflected in the ultrahigh value of ε′. The semicircular nature of the Nyquist plots is well explained by the cyclic movement of the charge and the high extent of charge storage. The significant improvement in dielectric properties in 1‐butyl‐3‐methylimidazolium hexafluorophosphate ionic liquid (IL)‐incorporated nanocomposite system reflects the coupling as well as dispersibility of IL. The reduction in ε′ and σac, and increase in bulk resistance with an increase in temperature indicate the positive temperature coefficient behavior of the developed nanocomposite systems. The adequate interaction between TiO2, TPU and PANI phases has been analyzed using X‐ray diffraction. The significant dispersing ability and coupling activity of the IL has been explored from micrographs obtained from a scanning electron microscopy study. © 2021 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Conductive rubber composites based on ethylene acrylic elastomer (AEM) and conductive carbon black (CCB) were prepared by a two-roll mixing mill. From the transmission electron microscope photomicrographs, the uniform distribution of CCB aggregates and the interconnected CCB aggregates in the AEM matrix were observed. The bound rubber content of unvulcanized rubber was found to increase significantly with increasing CCB content. The effect of CCB concentration on the dynamic viscoelastic properties of AEM matrix was determined using a Rubber Process Analyzer (RPA 2000) in terms of strain sweep and frequency sweep of both uncured and cured AEM/CCB systems. The storage modulus (G′) increased with an increase in CCB loading. In the case of strain sweep, the G′ values decreased with strain amplitude for both the systems, but the G′ was more for cross-linked AEM/CCB systems. The strain dependency of G′ for CCB-filled AEM systems can be explained on the basis of the Payne effect. The complex viscosity (η*) of these systems increased with CCB loading, and it decreased with strain amplitude, which is due to the shear thinning effect. The tan δ for unvulcanized and vulcanized systems increased with the strain; however, the value of tan δ was <1 throughout the experimental strain range, which explains the elastic nature of the cured systems. The G′ increased with angular frequency for both the systems and the tan δ became independent upon the angular frequency after 10 Hz. The alternating current conductivity (σAC) increased with an increase in CCB loading at all frequencies and the system achieves the percolation at 20 phr CCB loading, which is in accordance with the rheological percolation. The direct current conductivity (σDC) also increased with an increase in CCB concentration. [ABSTRACT FROM PUBLISHER]