Distinctive Contributions from Organic Filler and Relaxorlike Polymer Matrix to Dielectric Response of CuPc-P(VDF-TrFe-CFE) Composite

The dielectric response of copper-pthalocyanine (CuPc) oligomers embedded in a terpolymer matrix was discussed in different temperature regions. The two constituents, relaxorlike matrix and CuPc, determined the dielectric dynamics, although CuPc strongly increased the dielectric constant of the terpolymer at all temperatures. Two dielectric relaxations, both reflecting the charge carriers' response, were detected. One was ascribed to the nomadic polarization phenomenon and the other to a phonon assisted tunneling in CuPc. The temperature dependence of the dielectric response demonstrated that tunneling of polarons was the dominating charge transport mechanism in CuPc.