THERMALLY STIMULATED DEPOLARIZATION AND POLARIZATION CURRENT STUDY OFC-60-PU BASED CONDUCTING INTERPENETRATED POLYMER NETWORKS (IPNS)

Rubber-lire conductive polyaniline-polyurethane interpenetration netwo rks (IPNs) were synthesized by a sequence of poly condensation and dop ing reactions. The thermally stimulated depolarization and polarizatio n current (TSDC/TSPC) and the differential scanning calorimetry (DSC) techniques were used for the characterization of fullerenol-derived ur ethane copolymer and polyaniline/fullerenol-PU IPNs. Dual glass transi tions of fullerenol-derived polyurethane copolymers at -71 degrees C a nd 72 degrees C have been assigned as the motion of PTMO soft segment in the glassy state and the motion of network around fullerenol crossl inking sites respectively. A major crystal melting transition at -3 de grees C for all polyurethanes and an additional electric field induced crystal-crystal transformation at 17 degrees C of the fullerenol deri ved polyurethane network are seen. Within polyaniline/fullerenol-PU IP N, the network of polyaniline phase hinders the relaxation of higher T -g and the electric field induced crystal-crystal transformation. Phys ical aging treatment provides an indirect method for the characterizat ion of glass transitions of current network structure. TSDC technique provides a higher sensitivity in detecting structural relaxation and s erves as a direct measurement of phase transitions.