Search

In the current work electrical and ion transport parameters of polymer electrolyte (PE) system of chitosan (Ch)/poly(2-oxazoline) (POZ)loaded with various concentrations of lithium nitrate (LiNO3) salt were studied. The EIS analysis shows that the load of LiNO3 improves the conductivity of the PE. The depressed semicircle of EIS which its center is below the Zr-axis and the distribution of relaxation time (τ) of the electrolytes verify the non-Debye behavior of the electrolytes. The maximum conducting system (CSPZLI5) shows the highest conductivity of 1.46 × 10−3 S/cm. Transport parameters (number density (n), mobility (μ), viscosity (η), and diffusion coefficient (D) of ions) are measured by Trukhan and EIS methods and compared agreeably and it is also consistent with the conductivity results. The determined n value from EIS was found to increase from 1.69 × 1016cm−3 to 9.5 × 1019 cm−3. Distinguished areas of stability attributed to DC involvement were marked from AC spectra. Dielectric parameters (i.e. ε' and ε'') are high at the low-frequency (fr) window due to electrode polarization (EP). The loss tangent (tan δ) is used to measure the relaxation time (τ) and ion transport parameters. The τ for the PEs is set off to decrease with increase of LiNO3 amount. The minimum τ of 4.08 × 10−7 s confirms the LiNO3 role in increasing ion migration. The transport parameters (n, μ, D, and η) are also in relationship with the dielectric and impedance analyses. From electric modulus examination it is found that the EP contribution can be minimized and relaxation attributing to bulk effects can be highlighted.

Background/purpose: The purpose of this clinical study was to identify dielectric markers to complete a previous thermal and vibrational study on the molecular and organizational changes in human dermis during intrinsic and extrinsic aging. Methods: Sun‐exposed and non‐exposed skin biopsies were collected from 28 women devised in two groups (20‐30 and ≥60 years old). The dielectric relaxation modes associated with localized and delocalized dynamics in the fresh and dehydrated state were determined by the Thermostimulated currents technique (TSC). Results: Intrinsic and extrinsic aging induced significant evolution of some of the dielectric parameters of localized and delocalized dynamics of human skin. With photo‐aging, freezable water forms a segregated phase in dermis and its dynamics is close to free water, what evidences the major role of extrinsic aging on water organization in human skin. Moreover, TSC indicators highlight the restriction of localized mobility with intrinsic aging due to glycation, and the cumulative effect of chronological aging and photo‐exposition on the molecular mobility of the main structural proteins of the dermis at the mesoscopic scale. Conclusion: TSC is a well‐suited technique to scan the molecular mobility of human skin. It can be uses as a relevant complement of vibrational and thermal characterization to follow human skin modifications with intrinsic and extrinsic aging. [ABSTRACT FROM AUTHOR]

• Fabrication of polymer blends based on CS:POZ: with high ion transport. • Studies of electrical and dielectric properties. • The highest DC conductivity of 1.46 × 10−3 S/cm was achieved. • Calculation of ion transport parameters (n, μ and D) from EIS modeling and Trukhan method. In the current work electrical and ion transport parameters of polymer electrolyte (PE) system of chitosan (Ch)/poly(2-oxazoline) (POZ)loaded with various concentrations of lithium nitrate (LiNO 3) salt were studied. The EIS analysis shows that the load of LiNO 3 improves the conductivity of the PE. The depressed semicircle of EIS which its center is below the Z r -axis and the distribution of relaxation time (τ) of the electrolytes verify the non-Debye behavior of the electrolytes. The maximum conducting system (CSPZLI5) shows the highest conductivity of 1.46 × 10−3 S/cm. Transport parameters (number density ( n ), mobility ( μ ), viscosity ( η ), and diffusion coefficient ( D ) of ions) are measured by Trukhan and EIS methods and compared agreeably and it is also consistent with the conductivity results. The determined n value from EIS was found to increase from 1.69 × 1016cm−3 to 9.5 × 1019 cm−3. Distinguished areas of stability attributed to DC involvement were marked from AC spectra. Dielectric parameters (i.e. ε' and ε'') are high at the low-frequency (f r) window due to electrode polarization (EP). The loss tangent (tan δ) is used to measure the relaxation time (τ) and ion transport parameters. The τ for the PEs is set off to decrease with increase of LiNO 3 amount. The minimum τ of 4.08 × 10−7 s confirms the LiNO 3 role in increasing ion migration. The transport parameters (n , μ , D , and η) are also in relationship with the dielectric and impedance analyses. From electric modulus examination it is found that the EP contribution can be minimized and relaxation attributing to bulk effects can be highlighted. [ABSTRACT FROM AUTHOR]