Analysis of Disordered Dynamics in Polymer Nanocomposite Dielectrics for the Realization of Fractional-Order Capacitor

Abstract

In this work, analysis of disordered dielectrics is performed in light of partially conductive graphene nanosheets (GNS)/P(VDF) polymer nanocomposites. The analysis shows that the polymer composites with minimal conductivity can be employed as dielectrics for fractional-order capacitor (FOC). GNS weight percentage is varied from 3 to 13 wt% in P(VDF) matrix to track the onset and saturation of conductivity. Impedance spectroscopy of the samples is carried out in the frequency range of 100 Hz to 20 MHz along with XRD and Raman spectroscopy. The phase angle of the impedance varies from-84° to-46° with a maximum phase ripple of 5° over a frequency range of ~ 3 decades. The fractional-order ' ' of the complex impedance varies from 0.93 to 0.51. Nyquist and Bode plots for all the samples are fitted using Cole-Cole model for non-ideal dielectric response and the electrical equivalent circuit based on Cole-Cole model is obtained. The deviation from ideal capacitive behavior is monitored using the equivalent circuit data. Index Terms-fractional-order calculus, fractional-order capacitor (FOC), polymer composites, disordered dielectrics, GNS/P(VDF) composites, Cole-Cole model This work is focused on defining the dynamics of such polymers and their nanocomposites with conductive fillers. Disorder in such dielectrics is altered by changing the Manuscript

Viscoelastic and Properties of Amphiphilic Chitin in Plasticised Polylactic Acid/Starch Biocomposite

“…The single relaxation peaks of the DMA analysis can further be double-checked using the Cole–Cole analysis of viscoelastic response [ 44 , 45 ]. Cole–Cole is a method of analysing dielectric relaxation data that involves graphing E″ versus E′, with each point representing one frequency [ 45 , 46 ]. The Cole–Cole approach can be used to investigate the structural changes that occur in biocomposites once fillers are incorporated into the polymer matrix [ 46 , 47 ].…”

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