We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Dielectric and microwave shielding properties of three-phase composites graphite nanoplatelets/carbonyl iron/epoxy resin.
- Authors
Vovchenko, L. L.; Lozitsky, O. V.; Oliynyk, V. V.; Zagorodnii, V. V.; Len, T. A.; Matzui, L. Y.; Milovanov, Yu. S.
- Abstract
The electrical properties of three-phase composite materials (CMs) graphite nanoplatelets/carbonyl iron/epoxy resin (GNP/Fe/epoxy) with 30 wt% of Fe and (1–5) wt% of GNP were studied by measuring DC conductivity and AC impedance spectra in the frequency range up to 2 MHz. The microwave shielding properties were measured in the frequency range of electromagnetic radiation (EMR) 1–67 GHz. The Nyquist diagrams derived from measured impedance–frequency spectra for GNP/Fe/epoxy CMs were considered within the equivalent circuit model. The significant increase of permittivity was observed for three-phase CMs with the increase of GNP content compared to two-phase GNP/epoxy CMs. For example, the real part of permittivity ε ′ = 700–300 and imaginary part ε ″ = 4 × 105–300 for ternary 5 GNP/Fe/epoxy composite in the frequency range 1 kHz–2 MHz. The observed significant increase of AC conductivity for three-phase composites proved the synergetic role of Fe particles in dispersing of GNP filler in epoxy matrix and formation of micro-capacitor network (for low GNP content) as well as the conductive network for higher GNP content. The observed sufficient increase of EMR shielding ( SE T in dB) beginning from 30–35 GHz for GNP content of 3–5 wt% correlates with DC electrical conductivity increase. The increase of the sample thickness d leads to the increase of shielding efficiency mainly due to the increase of EMR absorption SE A term.
- Subjects
NANOPARTICLES; GRAPHITE composites; FREQUENCY spectra; NYQUIST diagram; ELECTROMAGNETIC radiation; GRAPHITE; EPOXY resins
- Publication
Applied Nanoscience, 2020, Vol 10, Issue 12, p4781
- ISSN
2190-5509
- Publication type
Academic Journal
- DOI
10.1007/s13204-020-01326-w