Distinctive contributions from organic filler and relaxorlike polymer matrix to dielectric response of CuPc-P(VDF-TrFE-CFE) composite

The dielectric response of copper-phthalocyanine (CuPc) oligomers embedded in a poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) terpolymer matrix was studied. Although admixture of CuPc strongly increases the dielectric constant of the terpolymer at all temperatures, each of the two constituents determines the dielectric dynamics in a different temperature region-the relaxorlike matrix above and CuPc below the terpolymer's freezing temperature. Two relaxations, reflecting the charge carriers' response in CuPc, were detected. Results on ac conductivity reveal that the tunneling of polarons is the dominating charge transport mechanism.