TITLE:
Complex Permittivity and Permeability Studies Viewing Antenna Applications of NBR-Based Composites Comprising Conductive Fillers
AUTHORS:
Abdullah G. Al-Sehemi, Ahmed A. Al-Ghamdi, Nikolay T. Dishovsky, Nikolay T. Atanasov, Gabriela L. Atanasova
KEYWORDS:
NBR Composites, Conductive Fillers, Antenna Applications, Complex Permittivity and Permeability
JOURNAL NAME:
Materials Sciences and Applications,
Vol.9 No.11,
October
26,
2018
ABSTRACT: The work presents studies
on the complex permittivity and permeability of composites based on
acrylonitrile butadiene rubber containing combinations of conductive fillers
which include carbon black and nickel powder. The properties of those
composites, containing each of the fillers at the same amount were compared.
The permittivity and permeability values of the composites are influenced
remarkably by their morphology and structure as well as by the morphological
and structural specifics of both fillers. As electron scanning microscopy
studies confirm, those parameters are predetermined by the nature of the
composites studied—particle size, particles arrangement in the matrix and their
tendency to clustering. Last but not least matrix-filler interface phenomena
also impact the characteristics in question. The possibilities for applications
of the composites in antennae have been studied, in particular, as substrates
and insulating layers in flexible antennae for body centric communications
(BCCs). The research results allow the conclusion that these materials can find
such applications indeed. Composites of higher conductivity can be used where
surface waves are generated to provide on-body communications, while composites
of lower conductivity may be used for antennae that will be on the body of a
person and will transmit to and receive from other antennas that are not on the body of the same person
(off-body communications). It is clear that one can engineer the properties of
antennae substrates at microwave frequencies by adjusting the filler content
and the type of filler and thus control and tailor the antenna performance
specific for a particular application.