Low Relaxation Time Research Articles

Using Poloxamer® 407 as Building Block of Amphiphilic Poly(ether urethane)s: Effect of its Molecular Weight Distribution on Thermo-Sensitive Hydrogel Performances in the Perspective of Their Biomedical Application

Due to its hydroxyl terminal groups, Poloxamer® 407 (P407), a commercially available poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymer can be used as macrodiol for the synthesis of high molecular weight amphiphilic poly(ether urethane)s (PEUs). This work was aimed at studying the effect of P407 purification by removing PEO-PPO diblock copolymer by-products on the chemical properties of PEU polymer and the physical properties of PEU hydrogels. Removal of PEO-PPO diblock copolymers (P407_P) was found to preserve the thermo-responsiveness of resulting hydrogels, although slightly lower gelation onset temperature (Tonset) was found for P407_P (15.3°C) vs. P407 (16.7°C) hydrogels (25% w/V) as assessed through temperature ramp test. P407 and P407_P were then reacted with 1,6-diisocyanatohexane and 1,4-cyclohexanedimethanol to synthesize two different PEUs, coded as CHP407 and CHP407_P, respectively. Lower Number Average Molecular Weight (Mn¯) and higher polydispersity Index (D) was measured for CHP407 (Mn¯: 34 kDa, D: 1.6) respect to CHP407_P (Mn¯: 40 kDa, D: 1.4) as a consequence of macrodiol purification. CHP407_P hydrogels formed bigger micelles (43.9 ± 4.1 nm vs. 28.7 ± 4 nm) while showed similar critical micellar temperatures (22.1°C vs. 21.6°C) respect to CHP407 formulations. Sol-to-gel transition of CHP407 and CHP407_P hydrogels was similar while CHP407_P gelation time at 37°C was longer as assessed by tube inverting test. The rheological analysis showed slightly lower Tonset for CHP407_P hydrogels (15% w/V), probably due to larger micelle size, promoting micellar assembly. However, CHP407_P hydrogels showed a significantly lower critical strain than CHP407 hydrogels, as assessed by strain sweep test, suggesting their higher brittleness due to a lower density of intermicellar bridge chains. Nano-scale hydrogel characterization by Low-Field Nuclear Magnetic Resonance spectroscopy supported previous findings, showing lower spin-spin relaxation time (i.e., 1,259 ms) for CHP407_P than for CHP407 hydrogels (i.e., 1,560 ms) at 37°C, which suggested the formation of a more tightly packed network for CHP407_P than CHP407 hydrogel. Finally, lower swelling capability and resistance against dissolution were measured for CHP407_P hydrogels. Overall, the here‐reported results suggested that the heterogeneous structure in the CHP407 hydrogel network caused by the presence of diblock copolymer-based macrodiols improved PEU hydrogel properties in light of their applicability in the biomedical field.

Proton conducting polymer electrolyte based on cornstarch, PVP, and NH4Br for energy storage applications

Proton conducting polymer blend electrolytes based on cornstarch and polyvinyl pyrrolidone (PVP) with ammonium bromide (NH4Br) were prepared by the technique of solution casting. Enhancement of amorphous nature by the addition of NH4Br has confirmed by XRD. In FTIR,by the addition of NH4Br salt in the optimized blend system, there occurs a change like altering the peak intensity, peak shape, and position. This reveals the appearance of complex formation between the polymer and salt. At 358 K, 30 wt.% of NH4Br added system shows the maximum conductivity (1.31 × 10−4 S cm−1). The conduction mechanism of higher conducting polymer blend electrolytes follows the quantum mechanical tunneling (QMT) at mid-frequency and overlapping large polaron tunneling (OLPT) at higher frequency. High dielectric constant and low relaxation time of ions in polymer chain are obtained for 30 wt.% of NH4Br added polymer blend electrolyte. From Wagner’s polarization technique, it is established that conduction present in the polymer electrolytes is predominately due to ions. Faradaic pseudo capacity behaviour has observed in higher conducting sample by cyclic voltammetry. The electrochemical cell has prepared by the higher conducting polymer electrolyte and the open circuit potential (OCP) of 1.24 V has achieved from prepared electrochemical cell.

Ventricular endomyocardial mitochondrial impairment and inflammation accompany diastolic dysfunction in the type 2 diabetic human heart

Abstract Type 2 Diabetes Mellitus (T2DM) is a major risk factor for chronic heart failure, even independent of coronary artery disease. Various underlying mechanisms worsening ventricular function in T2DM have been postulated based on data from animal studies, including mitochondrial abnormalities, alterations of Nuclear factor kappa-B (NfκB) expression, increased oxidative stress and inflammation and cardiac fibrosis and diastolic impairment. However, evidence in humans for these mechanisms is currently lacking. Especially early T2DM-related alterations and the impact of T2DM in the absence of coronary artery disease remain unclear. We hypothesize that T2DM (I) leads to distinct changes in diastolic cardiac function, (II) impairs mitochondrial function of the ventricular myocardium, and (III) increases ventricular myocardial NfκB expression. Heart transplant recipients with T2DM (“T2DM”, n=17) and without (“Non-DM”, n=32) T2DM (as determined by oral glucose tolerance tests) were included, if they had received their heart from a donor without Diabetes Mellitus. Thus, diabetes-exposure of the transplanted hearts exactly corresponded to the time since transplantation. Magnetic resonance imaging was performed to assess left ventricular ejection fraction, global longitudinal strain (GLS), diastolic strain, and T2 relaxation times, a marker of myocardial edema. We assessed NfκB p105 subunit (NfκB1) mRNA expression using real-time PCR and myocardial mitochondrial respiration using high-resolution respirometry in ventricular endomyocardial biopsies. All participants had normal left ventricular ejection fraction (LVEF) without angiographic signs of coronary artery disease post transplantation (average 2.9±2.4 years). Age, sex distribution and LVEF were comparable between T2DM and Non-DM participants (p=0.50, 0.40 and 0.36, respectively). While GLS was not different (p=0.34), T2DM exhibited lower diastolic strain (1.0±0.4 vs. 1.4±0.4s-1, p<0.01) and higher T2 relaxation times (67±3 vs. 64±3ms, p<0.05) than Non-DM, indicating impaired diastolic function and increased myocardial edema. In T2DM, myocardial mitochondrial respiration with fatty acids and glycolytic substrates was 22–27% lower and mitochondrial uncoupling was 19% higher, whereas ORP and TBARS were 17% and 34% higher than in Non-DM (all p<0.05). Myocardial oxidative capacity related negatively to fasting blood glucose (r=−0.35; p<0.01), and positively to insulin sensitivity (r=0.49; p<0.05) across all participants. Myocardial NfκB mRNA expression was 60% higher in T2DM (0.45 [0.29; 0.71] vs. 0.28 [0.21; 0.44] AU, p<0.05) and correlated inversely with complex I respiration (r=−0.33; p<0.05). Exposure to T2DM diminishes mitochondrial function in ventricular myocardium, which relates to hyperglycemia, insulin resistance, oxidative stress, inflammation, and ventricular diastolic dysfunction and edema. These changes appear within short-term overt diabetes and might precede T2DM-related heart failure. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was supported by funding from the German Research Council (SFB1116) and a grant provided by the research commission of the Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany.

ZnO-assisted synthesis of lignin-based ultra-fine microporous carbon nanofibers for supercapacitors

Reducing the material size could be an effective approach to enhance the electrochemical performance of porous carbons for supercapacitors. In this work, ultra-fine porous carbon nanofibers are prepared by electrospinning using lignin/ polyvinylpyrrolidone as carbon precursor and zinc nitrate hexahydrate (ZNH) as an additive, followed by pre-oxidation, carbonization, and pickling processes. Assisted by the ZnO template, the pyrolytic product of ZNH, abundant micropores are yielded, leading to the formation of microporous carbon nanofibers with specific surface area (SSA) up to 1363 m2 g−1. The average diameter of the lignin-based ultra-fine porous carbon nanofibers (LUPCFs) is effectively controlled from 209 to 83 nm through adjusting the ZNH content. With good flexibility and self-standing nature, the LUPCFs could be directly cut into electrodes for use in supercapacitors. High accessible surface, enriched surface N/O groups, and reduced fiber diameters endow the LUPCFs-based electrodes with an excellent specific capacitance of 289 F g−1. The reduction of fiber diameters remarkably improves the rate performance of the LUPCFs and leads to a low relaxation time constant of 0.37 s. The high specific capacitance of 162 F g−1 is maintained when the current density is increased from 0.1 to 20 A g−1. Besides, the fabricated LUPCFs show exceptional cycling stability in symmetrical supercapacitors, manifesting a promising application prospect in the next generation of supercapacitors.

Dielectric spectroscopy and electrical conductivity measurements on high-tilted antiferroelectric materials

ABSTRACT Dielectric spectroscopic measurements have been reported on three synthesized pure liquid crystalline compounds having paraelectric (SmA*), ferroelectric (SmC*) and antiferroelectric (SmCA*) phases in the frequency range of 40 Hz–25 MHz. Several relaxation modes i.e. low-frequency PL Mode and high-frequency PH Mode in the SmCA* phase, Goldstone Mode (GM) in SmC* phase and Soft Mode (SM) in SmA* phase have been observed. These materials with wide antiferroelectric range are found to possess low relaxation times, thus making them promising materials for applications. The Cole–Cole plot shows the modes in the SmCA* phase to be much weaker than in the SmC* phase. Dielectric loss is maximum in SmC* phase due to the Goldstone Mode. Additionally, the AC electrical conductivity is found to be maximum in the SmC* phase and is dependent on the frequency. Maximum DC conductivity of these materials is of the order of 10−5 Ohm−1 m−1.

Analysis of quality and microstructure of freshly potato strips fried with different oils

The quality of French fries is a key factor which affect consumer's willingness to buy it. During this study, the effects of ten commercial edible oils on the content and status of water and oil, color, texture, volumetric shrinkage and microstructure of freshly fried fries were investigated. Fries fried in rice bran oil had higher water content, volumetric shrinkage, hardness, luminosity and yellowness, as well as lower oil content and redness than those fried in other oils. Lower transverse relaxation time was observed in fries fried with high-oleic sunflower oil. Scanning electron microscopy revealed a severely damaged internal structure. Magnetic resonance imaging visualized a thicker crust in freshly fried fries. Sensory results indicated that the fries fried in rice bran oil had a superior mouthfeel and a lower oil content compared to those fried with other oils. This work can provide a useful reference for the consumers to choose appropriate oil when preparing the fries.

Boronate-ester crosslinked hyaluronic acid hydrogels for dihydrocaffeic acid delivery and fibroblasts protection against UVB irradiation

Herein, we exploit the dynamic nature and pH dependence of complexes between phenylboronic acid and diol-containing molecules to control the release of an anti-photoaging agent, dihydrocaffeic acid (DHCA), from a dynamic covalent hydrogel (HG). The HG is prepared by reversible formation of boronate ester crosslinks between hyaluronic acid (HA) modified with saccharide (GLU) residues and HA functionalized with 3-aminophenylboronic acid (APBA), part of which is involved in complexation with DHCA. The hydrogel exhibited increased dynamic moduli and a lower relaxation time at pH 7.4 in comparison to pH 6, and greater amount of DHCA was incorporated at pH 7.4. Moreover, this hydrogel prolonged DHCA release at pH 7.4 through drug reversible complexation/decomplexation, while the rate of release was fastest in acidic (skin) conditions. Very interestingly, the incorporation of DHCA into the network enhances its protection against UVB-induced L929 fibroblast death. Therefore, this smart hydrogel can contribute to photoaging prevention.

Effect of pH and mixing ratio on interpolymer complexation of scallop (Patinopecten yessoensis) male gonad hydrolysates and κ-carrageenan

The electrostatic complex coacervation between scallop Patinopecten. yessoensis male gonad hydrolysates (SMGHs) and κ-carrageenan (κ-C) were monitored by using turbidimetry at various pH (1–12) and biopolymer mixing ratio (9:1–1:9). The pHc exhibited ratio-independent behavior, and pHφ1, pHmax exhibited ratio-dependent behavior, respectively. The decreasing ratio enhanced the gel strength of SMGHs/κ-C at higher pH while inversely at lower pH, ascribing to more SMGHs aggregates and stronger neutralization between positively charged patches in SMGHs and κ-C at lower pH and higher ratio. Moreover, SMGHs/κ-C gel at acid condition exhibited lower relaxation times (T21 and T23). Furthermore, the rheological and relaxation time T2 data were well associated with microscopy images which indicated that SMGHs/κ-C gel showed a well-distributed network structure at more acidic domains, supporting stronger gel rigidity and water-holding capacity.

Ion transport, dielectric, and electrochemical properties of sodium ion-conducting polymer nanocomposite: application in EDLC

The present paper reports the investigation of structural, electrical, dielectric, and transport properties of the polyethylene oxide (PEO)-based polymer nanocomposite (PNC), with sodium hexafluorophosphate (NaPF6) salt and barium titanate (BaTiO3) as nanofillers. The PNC has been prepared via standard solution casting technique. The structural investigation has been investigated by X-ray diffraction and evidence the enhancement in amorphous content. The morphology has been examined by Field emission scanning electron microscopy technique and confirms the composite formation. The presence of polymer–ion and ion–ion interaction has been confirmed by the Fourier transform infrared spectra (FTIR) and evidences the PNC formation. The impedance spectroscopy has been performed to evaluate the ionic conductivity in the temperature range 40–100 °C. The increase of conductivity is obtained with the addition of nanofiller and temperature-dependent conductivity follows Arrhenius behavior. The PNC film having the highest conductivity exhibits low activation energy and indicates the fast ion migration. The ion transference number is close to unity and the voltage stability window is within the desirable limit. The complex permittivity and complex conductivity have been obtained and the plot has been fitted in the whole frequency window. The fitted plot is in perfect agreement with experimental data. The PNC having the highest conductivity has high dielectric strength and low relaxation time. It confirms the nanofiller role in enhancing ion migration. The ion transport parameters (n, μ, D) are also in correlation with impedance and dielectric analysis. The optimized PNC films have been used to prepare the Electric double-layer capacitors (EDLC) and it demonstrates the improved performance which may be attributed to the effective role played by nanofiller in boosting ion dynamics.

Processing of BiFeO3 thin films to control their dielectric response

BiFeO3 (BFO) thin films were studied to control their oxygen-related processing parameters in order to obtain specific electrical characteristics in terms of conductivity and dielectric relaxation. BFO thin films prepared with Fe and Bi excesses and post-annealed in oxygen atmosphere showed higher electrical conductivity and lower conduction activation energies than single phase ones. Distinct parameters indicated different conduction mechanisms in the films, associated with the first ionization of oxygen vacancies in BFO films with Fe and Bi excesses and the second one in single phase films. Higher conductive films show lower relaxation times compared to single phase ones.

Reducing phosphate in emulsified meat products by adding chia (Salvia hispanica L.) mucilage in powder or gel format: A clean label technological strategy

This study evaluated the functional properties of chia mucilage powder (MCP) and gel (MCG) as a phosphate replacers in low-fat Bologna sausages. Four treatments were produced without phosphates (F1–2% MCP; F2–2% MCG; F3–4% MCP; F4–4% MCG) and two with 0.25% phosphate (F5–2% MCG and F6–4% MCG) besides control (20%-fat-0.5% phosphate). Samples containing mucilage were less firm and less chewy on day 0, except F3. Treatments containing 2% MCG were judged acceptable and provided better emulsion stability than those with MCP. Adding 4% MCP or MCG resulted in Bolognas with lower relaxation times and more restricted mobility and lowest sensorial acceptance characterized by the terms light brown and dark pink color (F4). The microscopy images exhibited less cohesive structure in treatments with 4% of MCG, suggesting the formation of a weaker bound protein network. Chia mucilage gel at 2%, due to its functional properties, has proven to be a feasible strategy to substitute 50% phosphate in low-fat Bologna sausages.

Hybrid nickel ferrite nanotubes doped polyaniline nanocomposite and its dielectric properties

Nanotubes of nickel ferrite were prepared by citrate method and were used in nanocomposite synthesis via in situ polymerization technique. The structural and surface morphology characterization was carried out by FTIR, XRD, and SEM techniques. FTIR spectra show the characteristic peaks of benzenoid ring, quinoid ring, and nickel ferrite stretching of tetrahedral and octahedral sites. XRD pattern shows that NiFe2O4 nanotubes has a cubic spinal structure and remains undistorted even after dispersion in polyaniline matrix. The SEM image of 15% wt nanocomposite shows that the polyaniline coated nickel ferrite nanotubes form a length about 100 nm. Furthermore, the DC conductivity shows three steps conductivity feature and among all prepared nanocomposites, 15% wt one shows high conductivity of 1.89 S/cm. This is due to high absorption of activation energy 0.213 × 10−2 J/mol and elongation of nanocomposites chain length which is confirmed from the negative thermal coefficient graph. The VSM study shows the saturation magnetization decrease after formation of polyaniline nanocomposite. The dielectric properties were analyzed by impedance analyzer and it was found that 15% wt nanocomposite shows the lowest dielectric constant and dielectric loss as a result of high ac conductivity of about 1.32 S/cm which is due to sharp drop in bulk resistance and low relaxation time of 0.1375 µsec as evidenced from cole–cole plot.

Cadmium Sulfide Quantum Dots–Organometallic Halide Perovskite Bilayer Electrode Structures for Supercapacitor Applications

AbstractSupercapacitors are attracting great attention because of their fast charging–discharging ability as well as their high power density. The current research in this area focuses mainly on exploring novel low‐cost electrode materials with higher energy and power densities. In this work, thin‐film electrochemical capacitors were fabricated using layers of self‐synthesized cadmium sulfide quantum dots and organometallic halide perovskite materials as active electrodes. Organometallic halide perovskites exhibit interesting ionic responses as well as extraordinary electronic properties. These properties are exploited in fabricating the electrochemical capacitors, and the devices showed excellent cycling ability with stable capacitance outputs beyond 4000 cycles. Impedance spectroscopy measurements revealed that perovskites do not only serve as active electrodes but also as solid electrolytes, thereby enhancing the capacitance of the devices and hence the energy densities. The layers provide high surface areas for electrolytes to access the electrode materials; reasonably low charge transfer resistance and small relaxation time were also observed. This work opens new opportunities for developing thin‐film supercapacitors using low‐cost electrode materials and employing a facile, inexpensive solution‐process coating.

Polyelectrolyte nanocomposite hydrogels filled with cationic and anionic clays

Polyelectrolyte nanocomposite hydrogels (NHGs) were synthesized. NHGs were formed from a polymer matrix composed of a cationic, anionic, and alkylated chitosan polymer modified with vinyl groups (ChAV) to achieve greater crosslinking. Cationic and anionic clays montmorillonite and hydrotalcite, respectively, were used as nanofillers to introduce electrostatic interaction with the matrix. NHGs were obtained via in situ polymerization. The ChAV and NHGs were then characterized. Based on X-ray diffraction and transmission electron microscopy results, the morphology of the nanocomposite was generally intercalated with some nanocomposites showing exfoliation. Rheological studies revealed improvements in shear modulus of NHGs with respect to hydrogel without clay. Lower relaxation times were noted as the clay content increased and it was attributed to the interactions between the clay sheets and the polymer. In conclusion the rheological properties of the material are improved with the addition of clay and the interactions present with the polymer matrix.

A.C. Recombination Velocity as Applied to Determine n<sup>+</sup>/p/p<sup>+</sup> Silicon Solar Cell Base Optimum Thickness

This work deals with determining the optimum thickness of the base of an n+/p/p+ silicon solar cell under monochromatic illumination in frequency modulation. The continuity equation for the density of minority carriers generated in the base, by a monochromatic wavelength illumination (λ), with boundary conditions that impose recombination velocities (Sf) and (Sb) respectively at the junction and back surface, is resolved. The ac photocurrent is deduced and studied according to the recombination velocity at the junction, to extract the mathematical expressions of recombination velocity (Sb). By the graphic technique of comparing the two expressions obtained, depending on the thickness (H) of the base, for each frequency, the optimum thickness (Hopt) is obtained. It is then modeled according to the frequency, at the long wavelengths of the incident light. Thus, Hopt decreases due to the low relaxation time of minority carriers, when the frequency of modulation of incident light increases.

Investigations of lithium ion conducting polymer blend electrolytes using biodegradable cornstarch and PVP

Solid polymer electrolytes used in energy storage devices based on Cornstarch and Poly (vinyl Pyrrolidone) blend incorporated with lithium acetate was prepared using the solution casting method. XRD results confirmed that the amorphous nature of the as-prepared polymer electrolyte was increased by addition of salt. 80 wt % Cornstarch/20 wt % PVP/60 wt % lithium acetate added polymer blend system attains better amorphous nature than others. At ambient temperature, 60 wt % of lithium acetate added system has better bulk conductivity of 3.52 × 10−5Scm−1 over the frequency range of 42 Hz to 1 MHz using AC impedance spectroscopy studies. The dielectric analysis is confirmed that the higher conducting sample was having high dielectric constant and low relaxation time for enhancing ions dynamic behaviour. The conduction mechanism of the higher conducting polymer electrolyte is explained by small polaron hopping and overlapping large polaron tunnelling conduction mechanism. From the argand plot, it is confirmed that higher conducting sample has low relaxation time.

Magnesium Perchlorate Mixed and Glutaraldehyde Crosslinked Potato Starch: An Economical and Flexible Electrolyte Membrane

AbstractEnvironment friendly polymer electrolyte systems are the most sought over option for cheap energy efficient storage devices. The present paper discusses the results of potato starch + Mg(ClO4)2 system which satisfy the technical and economical criteria to become a potential candidate for future electrolyte systems. The developed system has high ionic conductivity (≈2.01 × 10−2 S cm−1), low relaxation time (55 µs), and wide electrochemical stability window (≈3 V). The phase angle approaches −78˚ and maintains its value for 10 Hz to 1 kHz frequency range. The prepared electrolyte system, being free standing, flexible, and having the ability of being bended and twisted, is the suitable candidate for flexible electrochemical device fabrication. The equivalent series resistance is quite low (3.6 Ω) and high self‐resonance frequency ≈0.1 MHz, below which energy can be efficiently stored. Hence, the present study reports an economical, easy to handle, and environment friendly electrolyte system suitable for flexible electrochemical device fabrication.

Preparation and Characterization of Biopolymer Electrolytes Based on Pectin and NaNO3 for Battery Applications

Pectin based biopolymer electrolytes have been prepared with different concentrations of sodium nitrate by solution casting technique using distilled water as solvent. The amorphous nature of all the prepared biopolymer electrolytes is confirmed by X-ray diffraction studies. The FTIR studies confirm the complexation between polymer and salt. The ionic conductivity (2.7 × 10–9 S/cm) of pure pectin is enhanced to 4.2 × 10–6 S/cm by doping of NaNO3 salt. The dielectric properties of the pectin/NaNO3 electrolytes are also discussed. The prepared biopolymer electrolytes obey Arrhenius behavior with respect to temperature. The high ionic conductivity, low relaxation time (41.2 mS) and maximum cationic transference number are achieved for 9% of NaNO3 doped biopolymer electrolyte. This highest conductivity polymer electrolyte has been used to construct a battery.

Phononic thermal transport properties of C3N nanotubes

Reverse nonequilibrium molecular dynamics (RNEMD) is employed to study the phononic thermal transport properties of C3N nanotubes. We study the effect of nanotube length and diameter on the thermal conductivity and investigate the phonon transport transition from ballistic to diffusive regime in C3N nanotubes. It is found that the thermal conductivity of C3N nanotubes is significantly lower than those of carbon nanotubes across the entire ballistic-diffusive range. In addition, significantly lower ballistic to diffusive transition length (72–80 nm) is observed in C3N nanotubes compared to carbon nanotubes. The inspection of phonon dispersion curves shows that carbon nanotubes have stiffer acoustic modes than C3N nanotubes which results in lower group velocities for C3N nanotubes. Due to the presence of nitrogen atoms, the phonon mean free paths and relaxation times of C3N nanotubes are shorter than those of the carbon nanotubes. The combined effect of lower group velocities and relaxation times leads to the lower thermal conductivity of C3N nanotubes.

Hybrid Nickel Ferrite Nanotubes Doped Polyaniline Nanocomposite and Its Dielectric Properties

Nanotubes of nickel ferrite were prepared by the citrate method and were used in nanocomposite synthesis via in situ polymerization technique. The structural and surface morphology characterizations were carried out by Fourier-transform infrared spectroscopy (FTIR), x-ray powder diffraction (XRD), and scanning electron microscopy (SEM) techniques. FTIR spectra show the characteristic peaks of benzenoid ring, quinoid ring, and nickel ferrite stretching of tetrahedral and octahedral sites. XRD pattern shows the cubic spinal structure of NiFe2O4 nanotubes and it remaining undistorted even after dispersion in a polyaniline matrix. The SEM image of 15 wt.% nanocomposite shows that the polyaniline coated nickel ferrite nanotubes form a length about 100 nm. Furthermore, the DC conductivity shows three steps conductivity feature and among all prepared nanocomposites, the 15 wt.% shows high conductivity of 1.89 S/cm. This is due to high absorption at activation energy of 0.213 × 10−2 J/mol and elongation of nanocomposites chain length which is confirmed from the negative thermal coefficient (NTC) graph. The vibrating sample magnetometer (VSM) study shows the saturation magnetization decrease after formation of polyaniline nanocomposite. The dielectric properties were analyzed by impedance analyzer, and it was found that 15 wt.% nanocomposite shows the lowest dielectric constant and dielectric loss as a result of high ac conductivity of about 1.32 S/cm which is due to the sharp drop in bulk resistance and low relaxation time of 0.1375 μs as evidenced from the cole-cole plot.