a) b - École Polytechnique de Montréal

Narkis and co-workers extended and developed previous works about melt-blending PANI and
other general polymers in order to decrease the percolation threshold and increase mechanical
properties(Haba, et al., 2000; Narkis, et al., 2000a; Segal, et al., 2001). They compared
dispersion mixing (Figure 2-29a) and melt-blending process (Figure 2-29b)(Narkis, et al., 2000a)
and found a percolation threshold of less than 1% for the former case and approximately 20% for
latter case.
a) b)
Figure 2-29: Conductivity vs. concentration of PANI/polymer prepared via a) dispersion
mixing, b) melt-blending(Narkis, et al., 2000a)
Levon et al.(Levon, Margolina, & Patashinsky, 1993) were the first who suggested utilization of
three components instead of two. They introduced the term “double percolated” in a ternary
polymer blend consisting of a conductive polymer. Double percolated system was defined as the
connectivity in a hierarchical basis of a connected path within a connected path, the last of which
is conducting. Narkis et al.(Narkis, et al., 2000a) reported a ternary blend comprised of
(PS/DOP)/CoPA/PANI and showed that CoPA situates at the interface. They showed that PANI
preferentially locates at the CoPA phase demonstrating a double percolation phenomenon in
which PANI is encapsulated by CoPA. The conductivity of the blend as a function of
concentration of CoPA was studied (Figure 2-30).
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