I have a doubt whether to consider polyaniline as a normal material with complex permittivity or as lossy metal at 6GHz. Is there any standard reference to the complex permittivity of polyaniline at microwave frequencies?
Dear Thomas
Polyaniline exhibits conductivity about 10000 S/m. See e.g.
M. Popis , J. Krupka , I. Wielgus & M. Zagórska (2009): Measurements of
Microwave Conductivity of Conjugated Polymers and Their Blends, Ferroelectrics, 388:1, 5-9 To link to this article: http://dx.doi.org/10.1080/00150190902963658
This means that at 6 GHz the imaginary part of
permittivity associated with conductivity Imag(relative_permittivity) =
sigma/(omega*eps_0) is about 30000
If so, the real part of permittivity becomes irrelevant and
it does not matter if you assume that it is 1 or 10 in any formulae
associated with MW wave propagation.
Furthermore the real part of permittivity is not measurable at
microwave frequencies, similarly as for metals.
On the other hand if you can obatin poor aniline sample having
sigma about 1 S/m then the real part of its permittivity would be
measurable and probably it will be the order of 3 as for non-conductive
polymers.
Thank you Professor Krupka for the guidance. Actually I need pellet of polyaniline of size 100mm^2 with a 4mm thickness. Wouldn't the conductivity depend upon the pressure that is used to compress the polyaniline powder to pellet? Is it possible to get these proposed conductivities in pellets with these dimensions? If so how is it achieved?
- Badges
- Science method
- Similar topics
- Methodology