We report the charge transport and the structural properties of nanocomposi
tes of polyaniline (PAN) with inorganic clay (Na+-montmorillonite), which w
ere synthesized by using a emulsion polymerization method. Dodecylbenzenesu
lfonic acid (DBSA) and camphorsulfonic acid (CSA) were used to dope the PAN
samples. In the X-ray diffraction patterns of the systems, we observed tha
t the layer of conducting PAN-DBSA or PAN-CSA between the clay layers was i
n nanoscale layers (< 10 Angstrom). The de conductivity (sigma(dc)) of PAN-
DBSA with the clay was similar to 10(-1) S/cm and that of PAW-CSA with the
clay was similar to 1 S/cm, at room temperature. The temperature dependence
of both systems followed a quasi-one-dimensional variable-range-hopping mo
del. In electron paramagnetic resonance (EPR) experiments, we measured the
temperature dependence of the EPR linewidth (Delta Hp-p) and of the signal
intensity of the systems. The doping level of the systems was obtained from
the ratio of the area of the nitrogen X-ray photoelectron spectroscopy (XP
S) peak to that of the sulfur XPS peak. The charge transport, the spin dyna
mics, and the structure properties of PAN-DBSA without the clay, which was
synthesized through the same emulsion polymerization method, were compared
to the PAN-DBSA samples with clay samples.