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This study investigates the effect of functionalized nanoclay on dielectric properties in the X‐band (8.2‐12.4 GHz) of synthesized nitrogen‐doped carbon nanotube (N‐CNT)/nanoclay/polyvinylidene fluoride (PVDF) nanocomposites prepared via melt‐mixing. Montmorillonite nanoclay was functionalized by an aminosilane coupling agent, making the nanoclay more compatible with the organic polymer. N‐CNT was synthesized employing a chemical vapor deposition technique. Transmission electron microscopy and optical microscopy were used to assess the morphology of nanocomposites. The incorporation of nanoclay improved the dielectric properties, that is, dissipation factor of N‐CNT/PVDF nanocomposites. For instance, incorporation of 0.5 wt% nanoclay into N‐CNT/PVDF nanocomposite at 1.0 wt% N‐CNT loading resulted in 61% reduction in the dissipation factor (from 0.18 ± 0.01 to 0.07 ± 0.01). The percolation threshold increased from 0.3 to 1.0 wt% of N‐CNT by incorporation of 0.5 wt% nanoclay, which expanded the percolation region. In addition, incorporation of 0.5 wt% nanoclay reduced agglomeration area ratio of 1.0 wt% N‐CNT/PVDF nanocomposite by 57%. Rheological results indicated collapse of N‐CNT networks upon addition of nanoclay to the N‐CNT/PVDF nanocomposite, which confirmed the dielectric results. Nitrogen heteroatoms (scattering centers) and functionalized nanoclay were responsible for reducing the dissipation factor.

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In this study, we investigate the use of asphaltene, a natural waste product that is inevitably formed during heavy oil processing, as a filler in polymer composites. The focus of this work is on the compatibility of various asphaltenes, featuring different polarities, with several polymers, including polypropylene (PP), polystyrene (PS), polymethyl methacrylate (PMMA), and polycarbonate (PC). The Hansen solubility parameters were plotted to predict the compatibility of polymers with different asphaltenes. Then, polymer composites were prepared by two common techniques: melt mixing and solution mixing. The dispersion state of the asphaltenes in each polymer was investigated by using imaging and rheological techniques. This work showed that the network structure of the asphaltenes and, thus, the final properties of the composites can be controlled by the polarity of asphaltenes, mixing technique, and melt viscosity