Dispersion polymerization using CMC as steric
stabilizer in water resulted in macroscopic precipi!
tation of PANI particles when the amount of
stabilizer was Q0 wt)[ However using high amount
of stabilizer i[e[ q4 wt) stable dispersions can
be obtained[ Presumably the very high viscosity of
these concentrated CMC solutions help to prevent
sedimentation of the particles[ Table 1 gives the
amounts used for the dispersion polymerization of
aniline in aqueous medium and the characterization
data of CMC!PANI composite particles[ It is evident
from the data that incorporation of CMC in the
colloid particles increases with decreasing aniline
concentration "and consequently also APS concen!
tration# in the reaction mixture when the CMC
concentration was kept constant[ The conductivity of
the CMC and PANI composite is lower than that of
pure PANI "entry no 0#[ In general conductivity
decreases as the percentage of nonconducting CMC
in the composite particles increases[ As the adsorbed
amount of stabilizer increases the _lm!forming
property of the CMC!PANI composite also in!
creases[