A series of novel conducting interpenetrating polymer networks (IPNs)
was prepared by sequential polymerization of maleimide-terminated poly
urethane (UBMI) and polyaniline (PANI) which was doped with dodecylben
zenesulfonic acid (PANIDB). From the differential scanning calorimetry
(DSC) analysis of the IPNs, the compatibility of the polyether-type U
BMI with PANIDB was better than that of the polyester-type UBMI with P
ANIDB. The IPNs exhibited higher conductivity and better mechanical pr
operties when the polyether-type UBMIs were used in the composition. T
he scanning electron microscopy (SEM) of the IPNs illustrated heteroge
neous structure of the cured resins when the polyester-type UBMI was i
ncorporated in the UBMI/PANIDB IPNs. Scanning tunneling microscopy (ST
M) images of the compatible polyether-type PANIDB/UBMI IPNs indicated
that the conducting region of the PANIDB was distributed as continuous
conducting networks in the matrix, which resulted in higher conductiv
ity and very low threshold concentration of the PANIDB for the conduct
ing IPNs.