Dielectric Permittivity Data Research Articles

Universal measuring cell and installation for determining dielectric parameters during the transition from a liquid oligomer to a solid polymer

This paper presents the design of a new installation and a universal measuring cell that allows determining the dielectric properties of materials in various states of aggregation.The data of dielectric permittivity studies for the initial components of the oligomeric binder, ED-20 epoxy oligomer and aminetype hardener triethylenetetramine (TETA), as well as the kinetics of its curing process, established by the change in dielectric permittivity, were obtained for the first time. It is also shown that the maximum temperature of the curing reaction of the ED20+TETA system can be determined from dielectric permittivity data.

Sb dopant-induced modifications in CuO–ZnO nanocomposites: Optical, electrical and magneto-dielectric insights for optoelectronic applications

This study involves the synthesis of CuO–ZnO nanocomposites with varying Sb doping levels (0%, 2.5%, and 5%) through a facile sol-gel process. Structural analysis via X-ray diffraction confirmed the presence of ZnO's hexagonal wurtzite phase and CuO's monoclinic phase in all samples, indicating reduced crystallinity due to doping. The average crystallite size was determined using Scherrer's formula, revealing a decrease in size with doping (33 nm, 31 nm, and 30 nm for 0%, 2.5%, and 5% Sb, respectively). Morphology and chemical composition were assessed using field emission scanning electron microscopy, and energy dispersive X-ray analysis. The optical bandgap of the Sb-doped CuO–ZnO nanocomposites was determined using a Tauc plot, resulting in values of 2.48 eV, 2.39 eV, and 2.32 eV for dopant concentrations of 0%, 2.5%, and 5%, respectively. Dielectric permittivity and tangent loss were studied across the frequency range of 100 Hz to 1 MHz at different temperatures ranging from 303 K to 723 K measured between 100 Hz and 1 MHz frequency, revealing Maxwell-Wagner-type interfacial polarization. The dielectric permittivity data reveal anomalous behavior near 673 K, shifting with doping, and is explained by thermal ionization and relaxation mechanisms. The ac conductivity, which varies with frequency, demonstrates low-frequency dispersion and is effectively described by Jonscher's power law aligned with the dielectric analysis. Magneto-dielectric measurements showed a positive effect for permittivity and a negative effect for tangent loss, which may be caused by the changes in dipole alignment. The magneto-dielectric effect was further explored by analyzing the impact of magnetic fields (0–1.5 T) on impedance spectroscopy. Nyquist plots obtained at various magnetic fields were fitted using parallel combinations of resistance-capacitor circuits. These plots were then employed to estimate the contributions of both grains and grain boundaries. Overall, the findings from this study provide a foundation for the development of multifunctional materials with tailored properties for a wide range of optoelectronic devices.

Composition design of BNBT-ST relaxor ferroelectric ceramics in superparaelectric state with ultrahigh energy density

BNT-6BT-based lead-free ceramics have gained significant attention due to their relatively large piezoelectric coefficients and tunable morphotropic phase boundary conditions. In this investigation, SrTiO3 (ST) was added to BNT-6BT ceramics to fabricate the BNT-6BT-xST (BNBT-xST) composition. The impact of ST content on the phase structure and dielectric permittivity of the BNBT-xST ceramics was studied. The XRD refinement data show that with increasing ST content, the crystal structure of BNBT-xST ceramics was transformed from the morphotropic phase structure (coexisting tetragonal (P4/mmm) and pseudo-cubic (Pmm) phase) to the pseudo-cubic phase. The dielectric permittivity data of the BNBT-80ST showed that the Tm (the maximum permittivity temperature) moved to −61.9 °C, which caused the room temperature to fall within the range of Tm < T < TB (the Burns temperature). This makes the BNBT-80ST a superparaelectric state in relaxor ferroelectrics (RFE). Furthermore, the maximum energy density and the charge-discharge efficiency of the BNBT-80ST achieved 5.48 J/cm3 and 87% at 495 kV/cm, respectively. The energy density of the BNBT-80ST was improved by 2.97-fold and 49% compared with that of the BNBT-30ST and BNBT-70ST. This is mostly attributed to weakened ferroelectricity and improved paraelectricity in the BNBT-80ST. This investigation demonstrates that BNBT-xST ceramics can be adjusted to a superparaelectric state with an ST content of 80%. This makes the material to possess both a large polarization and a high breakdown field. This material holds great promise for high energy density capacitor applications.

Oxygen–Ion Conductivity, Dielectric Properties and Spectroscopic Characterization of “Stuffed” Tm2(Ti2−xTmx)O7−x/2 (x = 0, 0.1, 0.18, 0.28, 0.74) Pyrochlores

Tm2(Ti2−xTmx)O7−x/2 (x = 0, 0.1, 0.18, 0.28, 0.74) solid electrolytes have been investigated as potential electrolyte materials for solid oxygen fuel cells (SOFCs), operating in the medium temperature range (600–700 °C). The design of new oxygen-conducting materials is of importance for their possible utilization in the solid oxide fuel cells. The oxygen–ion conductivity of the Tm2(Ti2−xTmx)O7−x/2 (x = 0, 0.1, 0.18, 0.28, 0.74) “stuffed” pyrochlores ceramics was investigated by electrochemical impedance spectroscopy (two-probe AC) in dry and wet air. The synthesis of precursors via co-precipitation and the precipitate decomposition temperature have been shown to be of key importance for obtaining dense and highly conductive ceramics. At ~770 °C, the highest total conductivity, ~3.16 × 10−3 S/cm, is offered by Tm2Ti2O7. The conductivity of the fluorite-like solid solution Tm2(Ti2−xTmx)O7−x/2 (x = 0.74) is an order of magnitude lower. However, for the first time a proton contribution of ~5 × 10−5 S/cm at 600 °C has been found in Tm2(Ti2−xTmx)O7−x/2 (x = 0.74) fluorite. Until now, compositions with proton conductivity were not known for the intermediate and heavy rare earth titanates Ln2(Ti2−xLnx)O7−x/2 (Ln = Ho − Lu) systems. The use of X-ray diffraction (structural analysis with Rietveld refinement), optical spectroscopy and dielectric permittivity data allowed us to follow structural disordering in the solid solution series with increasing thulium oxide content. High and low cooling rates have been shown to have different effects on the properties of the ceramics. Slow cooling initiates’ growth of fluorite nanodomains in a pyrochlore matrix. The fabrication of such nanostructured dense composites is a promising direction in the synthesis of highly conductive solid electrolytes for SOFCs. We assume that high-temperature firing of nanophase precursors helps to obtain lightly doped “stuffed” pyrochlores, which also provide the high oxygen–ion conductivity.

Hydrogeophysical characterization and determination of petrophysical parameters by integrating geophysical and hydrogeological data at the limestone vadose zone of the Beauce aquifer

The hydrological characterization of the vadose zone remains a major challenge considering the spatiotemporal variability of its properties and the limitations associated with hydrological measurements techniques. Geophysical methods, in particular the DC-resistivity and ground penetrating radar, can provide large scale images of hydrogeological structures and a non-invasive assessment of the subsurface dynamic processes. However, these approaches rely on the accuracy of the petrophysical relationships connecting the geophysical parameters to hydrogeological ones, where the site-specific determination of the associated petrophysical parameters is considered crucial. The first objective of this study was to investigate the relationship between the water content, geological properties, and geophysical attributes at the vadose zone of a vulnerable limestone aquifer. The second objective aimed to obtain the Archie’s and Complex Refractive Index Model (CRIM) petrophysical parameters by using borehole electrical resistivity and cross-hole ground penetrating radar data. For this purpose, we adopted a grid search inversion algorithm where the field geophysical data were integrated with water content profiles simulated by using HYDRUS-1D. The vadose zone profile was divided into three layers, and the inversion was carried out for the petrophysical parameters in each of the model layers. The electrical resistivity and relative dielectric permittivity data showed a very good correspondence with the simulated and experimental water content distributions along the vadose zone profile. The petrophysical parameters estimated by the inversion showed values that fall in the ranges reported in the literature. Similar values have been observed in the different model layers, with slight differences that were attributed to the vertical heterogeneities associated with the alteration and fracturation features of the limestone vadose zone. This study showed a very good correlation between geophysical, hydrogeological and geological data, and highlighted the presence of heterogeneities that can have profound effects on the vadose zone water dynamics.

Magnetic complexity, magnetodielectric effect and DFT calculations on correlation driven Gd2CoMnO6 insulator

In the family of Re2CoMnO6 manganite double perovskites, in contrast to parent La2CoMnO6 compound, Gd2CoMnO6 exhibits multiple magnetic transitions; ferromagnetic (FM) ordering, TC ∼ 112 K followed by AFM transition, TN ∼ 47 K, Gd spins ordering for T < 10 K and large isothermal entropy changes. A study of DC field-superimposed AC magnetic susceptibility measurements revealed the field-induced magnetic glassy behavior below TC and enhancement of FM correlations above TC. From the analysis of Almeida-Thouless behavior and dynamical power-law fit to frequency dependent AC susceptibility, Gd2CoMnO6 exhibits a volume spin glass-like nature below the freezing temperature, Tf ∼ 117.5 K. The isothermal field-dependent magnetic and dielectric permittivity data and temperature dependent Raman measurements (reported in ref. R. X. Silvaet al., J, Appl. Phys. 114 194,102 (2013)) confirms the spin-phonon coupling induced magnetodielectric effect. Further, the ground-state electronic structure and magnetic properties of Gd2CoMnO6 are investigated using DFT + U formalism with Vienna Ab-initio Simulation Package (VASP) code and predicted the material to be a correlation-driven insulator. The correlation value of the Hubbard U parameter at the 4f-Gd elements changes the stability of the magnetic state from Ferri to FM spin alignment for Ueff ≥ 3 eV and is correlated to the experimentally observed field-induced transformation of the short-range-order FiM/spin-glass-like phase into the long-range ordered FM phase.

Electromechanical properties of paper‐derived potassium sodium niobate piezoelectric ceramics

AbstractThe small‐signal dielectric and piezoelectric coefficients of paper‐derived sodium potassium niobate, K0.5Na0.5NbO3 (KNN), were compared with those of conventionally prepared samples. Results show similar functional properties of paper‐derived KNN without significantly decreasing the small‐signal piezoelectric coefficient. The structure and microstructure analysis of conventional KNN and paper‐derived KNN did not reveal any significant difference in the crystal structure and grain size. However, the temperature‐dependent inter‐ferroelectric phase transition temperature estimated from the temperature‐dependent dielectric permittivity data revealed a decrease of approximately 18°C for the paper‐derived KNN and is possibly associated with the structural and microstructural defects. This work indicates that optimizing suspension chemistry and sintering conditions will be critical to enhance the functional response of paper‐derived KNN further. Moreover, paper‐derived ceramic processing, a novel and cost‐effective additive manufacturing technology, can be potentially used to fabricate other electroceramics with a wide range of porosities and sizes as well as complex geometries and multilayer structures.

Significantly improved dielectric performance of bio-inspired gelatin/single-walled carbon nanotube nanocomposite

In this study, the dielectric properties of gelatin/single-walled carbon nanotube (Gel/SWCNT) nanocomposite were evaluated. The nanocomposites were synthesized by a simple solution casting method. The electron transport properties of the nanocomposites were studied by the dielectric and impedance spectroscopy techniques. A dielectric constant as high as 104 and a loss tangent of 0.91 were obtained for the Gel/SWCNT nanocomposite material at 100 Hz. The dielectric permittivity data of the nanocomposites were fitted by the modified Cole–Cole model to estimate the dielectric strength and the relaxation time. The addition of SWCNT into the gelatin reduces the relaxation time of the nanocomposite from 3.03 to 1.01 μs. The complex impedance spectra analyses show an increase in alternating current conductivity due to the incorporation of SWCNT and can be attributed to the change in bulk resistance together with a reduction in relaxation time of the nanocomposite. A quantitative analysis from the fitting of the Cole–Cole plot also reveals that the incorporation of SWCNT into the nanocomposite decreases the grain boundary resistance from 16 950 to 53 kΩ and increases the capacitive element from 67 to 275 nF. The mechanism behind the improved dielectric performance of the Gel/SWCNT nanocomposites has been elucidated in this study.

Frequency and temperature-dependent dielectric characteristics of lead-free Br doped perovskites (CH3NH3)3Bi2Cl9 and (CH3NH3)3Bi2BrxCl9-x

We report the synthesis and dielectric characteristics of lead-free methylammonium bismuth chloride (MABiCl) and Br doped methylammonium bismuth chloride (MABiBrCl) in powder form. The morphology of the samples showed growth of large flakes with large surface area. The band gaps of the perovskites are obtained from optical absorption data. The dielectric characteristics of the samples were measured in the frequency range 1 Hz to 1 MHz and temperature range 100–300 K. The data shows a complex electrical transport in these halide perovskite materials. The dielectric permittivity data shows the existence of a critical temperature at which the material undergoes a structural phase transition. The transition temperature is found to be 270 K and 266 K for MABiCl and MABiBrCl respectively. The results can be explained by certain change in orientation of methyl-ammonium (MA) ions as the temperature is increased.

Synthesis, Characterization, and Dielectric Study of Titania Supported ZnFe2O4

AbstractThe nanocomposites of TiO2 loaded ZnFe2O4powders are synthesized using wet chemical process. The synthesized powder is characterized by using XRD, TEM, and VSM. In the XRD patterns of sintered composite samples, no peaks other than TiO2 and ZnFe2O4 are observed. Nanosized two different layers such as cubic zinc ferrite and TiO2are confirmed by transmission electron microscopy technique. The dielectric properties are measured in the frequency range of 20 Hz–1 MHz. The frequency variation of dielectric properties is understood with the help of Maxwell–Wagner type of interfacial polarization, which is in agreement with Koop's phenomenological theory. Dielectric permittivity data reveals dielectric permittivity decreases with frequency and increases with TiO2 composition. The dielectric constant (ϵ′) is decreased continuously with increased frequency for all the samples at room temperature revealing normal dielectric behavior of ferrites. Magnetic properties are also measured on all the composite samples at room temperature. The saturation magnetization (Ms) of the samples decreases with an increase of TiO2content in ZnFe2O4.

Structural and Dielectric Properties of PVDF/6A Clay Nanocomposites

AbstractThe paper describes the study of structural and dielectric properties of PVDF blended with organically modified clay. The PVDF/clay nanocomposites are prepared by simple melt mixing method. The prepared nanocomposites are characterized for structural and dielectric properties. The structural characterization done using X‐ray diffraction and infra‐red spectroscopy techniques indicates the crystallization of ferroelectric β phase in nanocomposites. The dielectric study shows the composition‐dependent significant enhancement in the dielectric permittivity, particularly in the low‐frequency region. The enhancement in the dielectric permittivity is explained on the basis of increase in the conductivity and formation of minicapacitor‐like network in the nanocomposites. The dielectric loss spectra of PVDF shows two relaxations corresponding to the glass transition temperature and crystalline relaxation. In case of PVDF/Clay nanocomposites, the dielectric relaxation corresponding to the crystalline relaxation completely disappears, which is attributed to the dielectric manifestation of ferroelectric β phase in nanocomposites. The observed dielectric permittivity data can be very well fitted using Vo‐Shi model, which takes contribution of interphase to the dielectric permittivity. The enhancement in the dielectric permittivity along with ferroelectric β phase in PVDF/clay nanocomposites brings the potential application in energy storage devices.

Ionic Conductivity of Hybrid Composite Solid Polymer Electrolytes of PEOnLiClO4-Cubic Li7La3Zr2O12 Films

Ionic conductivity of the polyethylene oxide-LiClO4 (PEOnLiClO4) solid polymer electrolyte (SPE) films with an EO:Li ratio (n) of 10, 12, 15, as well as the hybrid composite solid polymer electrolyte (CSPE) films of PEOnLiClO4 containing 50 wt% of cubic-Li7La3Zr2O12 (LLZO) sub-micron sized particles, have been studied by varying Li-salt content in the films. The complex AC dielectric permittivity and conductivity data obtained from electrical impedance measurements were fitted using a generalized power-law, including the effects of electrode polarization applied at low AC frequencies to obtain various relaxation times. In addition to increased mechanical and thermal robustness, the CSPE films show higher values of ionic conductivity, &gt;10−4 S/cm at room temperature compared to those of SPE films with n = 12 and 15. On the contrary, the ionic conductivity of CSPE with n = 10 decreases by a factor of three compared to the corresponding SPE film due to increased polymer structural reorientation and Li-ion pairing effects. The Vogel–Tammann–Fulcher behavior of the temperature-dependent conductivity data indicates a close correlation between the ionic conductivity and polymer segmental relaxation. The PEO12LiClO4-LLZO film shows the lowest activation energy of ~0.05 eV.

Natural factors related to the differential heating of aggregates exposed to microwaves

The heating produced by microwaves has been demonstrated to be effective in materials such as aggregates, although notable differences in heating have been observed between different types of aggregates. The geological factors of each material are responsible for these differences in heating due to compositional elements such as the mineralogy and chemistry of the material and physical characteristics such as crystal size and apparent density.The study of each of these characteristics could unravel the factors determining differential heating in aggregates, which would be relevant for different applications in the mining industry (heating, drying, and comminution) and in civil engineering in self-healing (microcrack repair) or winter road maintenance (surface de-icing).This paper investigates the influence of microwave heating on the chemical, mineralogical, and physical properties of aggregates susceptible to be used in asphalt mixtures. For this, aggregates with different characteristics have been selected. Various tests were conducted to determine the factors affecting heating: thin-section studies (mineralogy and crystal size), XRD (mineralogy) and XRF (chemistry) composition studies, and bulk density of the rocks. These results were correlated with dielectric permittivity data (loss tangent) and direct heating data (parameter T70). Both techniques have proven helpful as an indicator of susceptibility to microwaves. Finally, multiple regression models were proposed to apply this knowledge to any rocks suitable as aggregate.

Multiferroicity in a quasi-one-dimensional magnet MnSb2Se4

We report a comprehensive study of the structural, magnetic, and multiferroic properties of a quasi-one-dimensional magnet, MnSb2Se4, crystallizing in a centrosymmetric monoclinic structure. Magnetic and heat capacity measurements revealed that this compound undergoes a long-range antiferromagnetic ordering at TN = 22.5 K. A dielectric anomaly appeared at the TN in the absence of a magnetic field, and, an applied magnetic field of 9 T induced another dielectric anomaly just below the TN. Furthermore, the pyroelectric and DC-bias current measurements confirmed that these anomalies are associated with spontaneous electric polarization, whose magnitude becomes almost double under an applied field of 9 T. These results demonstrated that MnSb2Se4 is a type-II multiferroic material with strong magnetoelectric coupling. Moreover, a frequency-dependent dielectric anomaly observed at 5 K in the real component of the dielectric permittivity and loss data indicates relaxor behavior.

Dielectric properties and thermally activated relaxation in monovalent (Li+1) doped multiferroic GdMnO3

Temperature and frequency-dependent dielectric properties of 15% monovalent Li doped multiferroic GdMnO3 sample have been studied. A thermally activated relaxation with activation energy ~ 0.17 eV has been determined. An excellent fit of frequency dependent dielectric permittivity data with Curie-Von Schweidler’s function having n < 1 indicates that only Non-Debye relaxation is present in our sample. The frequency response of ac conductivity has been analyzed by using the Jonscher’s universal power law and signifies that motions of charge carriers are translational type. The temperature dependence of conductivity $$\sigma_{{{\text{dc}}}}$$ and $$\sigma_{{{\text{ac}}}} (\omega )$$ both follows Arrhenius law. An increase in conductivity with an increase in temperature suggests that electrical conductivity in the material is a thermally activated process.

The Arctic soils dielectric characteristics

The state of the underlying surface has a noticeable effect on the process of emission and propagation of radio waves. The state of the underlying surface is dependent on the value of the complex dielectric permittivity. Usually, the underlying surface is understood as soil or ground medium. The Dobson model is recommended by the International Telecommunication Union (ITU) for calculating the dielectric permittivity of moist soils over a wide frequency range. However, this model was developed based on experimental data obtained at frequencies above 1 GHz for soils of the temperate climatic zone. This paper presents the results of measuring the complex dielectric permittivity of the Arctic region soils sample at the frequency range from 1 MHz to 8 GHz. Also, we compared the dielectric permittivity data measured in laboratory conditions and calculated by the Dobson model. It was found that the Arctic soil dielectric permittivity data measured under laboratory conditions and calculated using the Dobson model differ markedly from each other, which indicates the impossibility of using the Dobson model for calculating soil dielectric permittivity of the Arctic region. The data obtained in the laboratories case may be used to estimate the directional characteristics of near-surface emissivity systems, as well as of the ground wave propagation prediction in the Arctic region.

Thermophysical Properties of 1,1,1,3,3,3-hexafluoro-2-methoxypropane (HFE-356mmz) in the Vapor Phase Measured by Using an Acoustic-Microwave Resonance Technique

Thermophysical properties of HFE-356mmz in the vapor phase were measured by means of an acoustic-microwave resonance method. HFE-356mmz, which is 1,1,1,3,3,3-hexafluoro-2-methoxypropane in chemical name, is expected to be used as a working fluid with low global warming potential for the Organic Rankine cycle (ORC). The sound velocity and dielectric permittivity were simultaneously measured by using a cylindrical acoustic-microwave resonator. The sound velocity data were analyzed to obtain the ideal-gas heat capacity at constant pressure. The integral of the ideal-gas heat capacity as a function of temperature derives the ideal-gas enthalpy, which is a fundamental and important energy property to simulate the thermodynamic cycle. Similarly, the analysis of the dielectric permittivity data leads to information on the ideal-gas molar polarizability, dipole moment, and density. The acquired thermophysical properties of HFE-356mmz were compared to those of R-245fa and n-pentane, which are the existing working fluids for the ORC system, to prospect a feasibility of HFE-356mmz as their alternative.

Magnetic and electric behaviors of [formula omitted]: Effect of hole doping

DyMn2O5 is an intriguing multiferroic material showing multiple magnetic, electric and structural transitions. We present here the systematic study on the effect of Sr doping at the Dy site of DyMn2O5 through magnetic and dielectric measurements. Doping of divalent Sr at the Dy site is expected to enhance the Mn4+:Mn3+ ratio and it will also dilute the Dy site. Our study indicates large enhancement in the magnetic anomaly observed close to 43 K, which we believe to be related to the increased ferromagnetic correlations on Sr doping. Gradual increase in coercive field at 3 K with the Sr doping and decrease in bond length of adjacent Mn4+ ions further support the enhancement of ferromagnetic correlations in the system. The parent sample shows a large magnetocaloric effect around 12 K, the magnitude of which found to decrease with increasing Sr concentration. The doping also enhances the anomaly at around 28 K observed in the dielectric permittivity versus temperature data, and this anomaly was earlier claimed to be associated with the spin reorientation as well as a simultaneous transition from one ferroelectric state to other. The electric orderings observed below 25 K are found to be susceptible to the applied magnetic field, and supports the view of Ratcliff II et al. (Phys. Rev. B 72, 060407(R) (2005)) of concomitant changes in the magnetic structure associated with the multiple electric transitions.

Development of a Program for Analyzing Dielectric Relaxation and Its Application to Polymers: Nitrile Butadiene Rubber

To characterize the dielectric relaxation embedded in polymers, we developed a program algorithm that analyzes the relaxation processes from dielectric permittivity versus frequency data based on governing functions such as the Havriliak-Negami function including the conductivity contribution. With the help of the developed simulation program, we have identified three processes: an α process due to rotational and segmental motions of the C-C bond, an α’ process attributed to the fluctuation of the end-to-end dipole vector of the polymer chain, and the conduction contribution observed at high temperatures and low frequencies. The activation energy and glass transition temperature for the two main relaxations were independently determined from both the imaginary permittivity versus frequency and temperature by assuming Arrhenius dependence and the Vogel-Fulcher-Tamman law. The results obtained by the two methods for α and α’ relaxations were compared with each other and with that obtained by differential scanning calorimetry.

Effect of rGO:MWCNTs ratio on electrical conductivity of polyazomethine/rGO:MWCNTs nanocomposites

Using solution blending method, we produced nanocomposites based on polyazomethine (PAZ) loaded with hybrid carbon nanofillers. The nanofillers comprised reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNTs). The total nanofiller loading was equal to 1 wt% while the rGO:MWCNTs ratio varied as follows: 100:0, 75:25, 50:50, 25:75, and 0:100 wt%: wt%. The complex dielectric permittivity data obtained with a broadband dielectric spectrometer were used to analyze electrical conductivity of the nanocomposites in wide ranges of frequency and temperature. Electrical conductivity was found to increase with increasing MWCNTs portion and its maximum value was achieved when the nanofiller contained the MWCNTs nanoparticles exclusively. We extracted the electrical conductivity components, dc conductivity σdc and ac conductivity σac, and analyzed their behavior as function of frequency and temperature. The temperature dependences of σac were described with the Arrhenius equation, whereas its frequency dependences were characterized with a power function. For explaining the σac behavior, the correlated barrier hopping mechanism was accepted. Interfacial interactions between the hybrid nanofillers and the polymer matrix (the Maxwell-Wagner-Sillars effect) were detected. It was found to be strongly pronounced in the nanocomposites with high portion of MWCNTs in the hybrid fillers.