Anantharaman, M R; Saravanan, S; Joseph, Mathai C; Venkitachalam, S; Prabhakaran, P V(Wiley Periodicals, July 23, 2003)
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Abstract:
Electrically conductive organic and metalloorganic
polymers are of great interest and they have applications
in electronic, optical, photonic, photoelectric, electrochemical,
and dielectric devices. Tetrameric cobalt phthalocyanine
was prepared by conventional chemical method.
The dielectric permittivity of the tetrameric cobalt phthalocyanine
sample was evaluated from the observed capacitance
values in the frequency range 100 KHz to 5 MHz and
in the temperature range of 300 to 383°K. It is found that the
system obeys the Maxwell Wagner relaxation of space
charge phenomenon. Further, from the permittivity studies
AC conductivity was evaluated. The values of AC conductivity
and DC conductivity were compared. Activation energy
was calculated. To understand the conduction mechanism
Mott’s variable range hopping model was applied to
the system. The T 1/4 behavior of the DC conductivity along
with the values of Mott’s Temperature (T0), density of states
at the Fermi energy N (EF), and range of hopping R and
hopping energy W indicate that the transport of charge
carriers are by three-dimensional variable range hopping
Description:
Journal of Applied Polymer Science, Vol. 91, 2529–2535 (2004)
Anantharaman, M R; Soloman, M A; Philip, Kurian; Joy, P A(Wiley Periodicals, September 26, 2002)
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Abstract:
Fine particles of barium ferrite (BaFe12O19)
were synthesized by the conventional ceramic technique.
These materials were then characterized by the X-ray diffraction
method and incorporated in the natural rubber matrix
according to a specific receipe for various loadings of
ferrite. The rubber ferrite composites (RFC) thus obtained
have several applications, and have the advantage of molding
into complex shapes. For applications such as microwave
absorbers, these composites should have an appropriate
dielectric strength with the required mechanical and
magnetic properties. The N330 (HAF) carbon black has been
added to these RFCs for various loadings to modify the
dielectric and mechanical properties. In this article we report
the effect of carbon black on the mechanical and dielectric
properties of these RFCs. Both the mechanical and dielectric
properties can be enhanced by the addition of an appropriate
amount of carbon black
Description:
Journal of Applied Polymer Science, Vol. 89, 769–778 (2003)