Dielectric Relaxation in Biocomposites Based on Olive Pomace Grains
A polyester polymer matrix filled with olive-pomace grains was investigated using impedance spectroscopy in the frequency range 100 Hz to 1 MHz and temperatures from 300 to 360 K. Two relaxations processes were identified. One could be attributed to the α relaxation associated with the glass transition and observed in the neat matrix, while the second was attributed to the accumulation of charges at the pomace grains/polyester interfaces. The relaxation parameters were evaluated from isothermal dielectric spectra by applying the empirical Havriliak-Negami function.
KeywordsBiocomposites Dielectric relaxation Havriliak-Negami function
The authors acknowledge support from CNRST-Maroc (Centre National de la Recherche Scientifique et Technique) and the FCT-CNRST bilateral cooperation, and FEDER by funds through the COMPETE 2020 Program and National Funds through FCT – Portuguese Foundation for Science and Technology under the project UID/CTM/50025/2013.
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