An attempt has been made to tune the DC electrical conductivity and impedance characteristics of the nanocomposites by coating carbon nanotubes (CNTs). A microwave-assisted in-situ polymerization approach is utilized to coat the CNTs with polystyrene and no initiators are used. The nanocomposites are characterized by FE-SEM, TEM, FT-IR, Raman and TGA. Based on the morphological studies, a polystyrene layer is detected on the CNTs. According to the TGA results, the weight loss in the temperature range of polystyrene decomposition increases with increasing microwave irradiation time, suggesting a higher polystyrene content. Moreover, the DC electrical conductivity of the nanocomposites, as well as the real and imaginary impedance and dielectric permittivity are explored. It is shown that increasing the irradiation time decreases the DC electrical conductivity and dielectric permittivity but increases the real and imaginary impedance. Since the thickness of the polystyrene layer depends on the duration of microwave irradiation, our method can be used to tune the electrical conductivity and impedance characteristics. This can be applied to practical situations where a particular resistance is required.

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